Conferences
Members of our group participated in the following conferences.
2026
The Twenty Fifth Katowice-Debrecen Winter Seminar on Functional Equations and Functional Inequalities, Kościelisko-Zakopane, Poland, February 3-6, 2026
- Dorota Głazowska "Complementary means for generalized classical weighted means with respect to classical weighted means"
- Justyna Jarczyk "Iterates, fractional iterates and semiflows of Möbius transformations"
- Witold Jarczyk "When are local properties of solutions of iterative functional equations actually global?"
2025
21st International Conference on Functional Equations and Inequalities, Będlewo (Poland), September 14-20, 2025
- Dorota Głazowska "Weakly associative functions and means"
- Justyna Jarczyk "On a multiplicative iterative equation and its relationships to probability theory"
- Witold Jarczyk "On iterative roots of some multifunctions"
- Tomasz Małolepszy "On some functional equations related to Cauchy differences"
30th International Conference on Difference Equations and Applications, Guangzhou (China), July 15-19, 2025
- Justyna Jarczyk "Iterative roots and semiflows of mean-type mappings"
61st International Symposium on Functional Equations, Cluj-Napoca (Romania), June 15-21, 2025
- Dorota Głazowska "Remarks on invariance equations involving generalized classical weighted means"
- Justyna Jarczyk "Complex-valued solutions of a multiplicative equation of finite order"
- Witold Jarczyk "On iterative roots of mean-type mappings"
100th anniversary of the birth of Professor János Aczél, Hajdúszoboszló (Hungary), February 2-7, 2025
- Dorota Głazowska "Invariance problems for generalized classical weighted means"
- Janusz Matkowski "Weak associativity: new examples and open questions"
2024
60th International Symposium on Functional Equations, Kościelisko (Poland), June 9-15, 2024
- Dorota Głazowska "Weakly associative means"
- Justyna Jarczyk "Complex-valued solutions of an iterative functional equation of finite order"
- Witold Jarczyk "On an extension procedure for solutions of simultaneous q-difference equations"
- Tomasz Małolepszy "Separate and joint continuity of means"
- Janusz Matkowski "Lipschitz mappings and fixpoint principle in metrically convex spaces"
24th European Conference on on Iteration Theory (ECIT2024), Vimeiro (Portugal), May 27-31, 2024
- Dorota Głazowska "Subcommutativity of integrals similar to integral quasi-arithmetic means"
- Justyna Jarczyk "Complex-valued solutions of an iterative functional equations of finite order"
- Witold Jarczyk "Iterative roots of piecewise monotonic functions extended from the characteristic interval"
2023
20th International Conference on Functional Equations and Inequalities, Będlewo (Poland), September 17-23, 2023
- Dorota Głazowska "Subcommutativity of integrals similar to integral quasi-arithmetic means"
- Justyna Jarczyk " On a linear iterative equation of finite order and its solutions with a prescribed asymptotics"
- Witold Jarczyk "Iterative roots of piecewise monotonic functions extended from the characteristic interval"
59th International Symposium on Functional Equations, Hajdúszoboszló (Hungary), June 19-26, 2022
- Witold Jarczyk "On a functional equation characterizing some probability distributions"
2022
58th International Symposium on Functional Equations, Innsbruck (Austria), June 19-26, 2022
- Dorota Głazowska "Invariance equations involving generalized classical weighted means"
- Justyna Jarczyk "On various concepts of means and iterates of maps built of them, part I"
- Witold Jarczyk "On various concepts of means and iterates of maps built of them, part II"
European Conference on Iteration Theory, Reichenau an der Rax (Austria), July 13-17, 2022
- Witold Jarczyk "Gaussian iterative algorithm for various notions of means"
2021
19th International Conference on Functional Equations and Inequalities, Będlewo (Poland), September 12-18, 2021
- Dorota Głazowska "Generalized classical weighted means and some related problems"
- Justyna Jarczyk "On generalized Archimedes-Borchardt algorithm"
- Witold Jarczyk "Form of semiflows of pairs of weighted quasi-arithmetic means"
- Janusz Matkowski "Remarks on a fixed point theorem"
26th International Conference on Difference Equations and Applications, Sarajewo (Bosnia and Herzegovina), July 26-30, 2021
- Witold Jarczyk "On generalized Archimedes-Borchardt algorithm"
2020
20th Debrecen--Katowice Winter Seminar on Functional Equations and Inequalities, Hajdúszoboszló (Hungary), January 29-February 1, 2020
- Justyna Jarczyk "On a functional equation appearing on the margins of a mean invariance problem"
- Witold Jarczyk
2019
Dynamics, Equations and Applications (DEA 2019), Kraków (Poland), September 16-20, 2019
- Dorota Głazowska "Embeddability of pairs of weighted quasi-arithmetic means into a semiflow"
- Justyna Jarczyk "Gaussian algorithm for mappings built of parametrized means"
- Witold Jarczyk "Generalized Gaussian algorithm"
18th International Conference on Functional Equations and Inequalities (ICFEI'19), Kraków (Poland), June 9-15, 2019
- Mariusz Sudzik "Iterative functional equations and attractive fixed points"
57th International Symposium on Functional Equations, Jastarnia (Poland), June 2-9, 2019
- Dorota Głazowska
- Justyna Jarczyk
- Witold Jarczyk
- Tomasz Małolepszy "On Walter-Weckesser theorem"
- Mariusz Sudzik "The archetypal equation and its solutions attaining the global extremum"
24th International Conference on Mathematical Modelling and Analysis, Tallinn (Estonia), May 28-30, 2019
- Tomasz Małolepszy "On Bushell-Okrasiński inequality"
Progress on Difference Equations (PODE 2019), Bragança (Portugal), May 27-30, 2019
- Dorota Głazowska "Convexity in the class of weighted quasi-arithmetic means"
- Justyna Jarczyk "Generalized Gaussian algorithm"
- Witold Jarczyk "On some simultaneous geometric di↵erence equations"
2018
Numbers, Functions, Equations 2018, Hajdúszoboszló (Hungary), August 26 - September 1, 2018
- Dorota Głazowska "On weighted quasi-arithmetic means which are convex"
- Witold Jarczyk "Continuous solutions of some simultaneous difference equations on a restricted domain"
European Conference on Iteration Theory, Murcia (Spain), 3-6 July 2018
- Justyna Jarczyk "Joining means by iteration"
- Witold Jarczyk "Iterative roots of pairs of weighted quasi-arithmetic means and embeddability of such pairs into a semiflow"
56th International Symposium on Functional Equations, Graz (Austria), June 17-24, 2018
- Dorota Głazowska "Invariance of quasi-arithmetic mean with respect to a pair of weighted Bajraktarević means"
- Justyna Jarczyk "On symmetry of Makó-Páles means"
- Witold Jarczyk "Simultaneous difference equations on a restricted domain"
- Mariusz Sudzik "A problem of G. Derfel and its partial solution"
Dynamical Systems, Difference and Functional Equations. In honor of Marek C. Zdun's 70th birthday, Krynica-Zdrój (Poland), June 4-8, 2018
- Dorota Głazowska "Invariance of quasi-arithmetic mean with respect to weighted Bajraktarević mean-type mappings"
- Justyna Jarczyk "Joining means by iteration"
- Witold Jarczyk "Embeddability of pairs of weighted quasi-arithmetic means in a semiflow"
- Mariusz Sudzik "An equation with rescaling and its solutions attaining an absolute extreme"
23rd International Conference on Mathematical Modelling and Analysis, Sigulda (Latvia), May 29 - June 1, 2018
- Tomasz Małolepszy "Volterra integral equations in the nonlinear diffusion theory"
2017
International Conference on Analysis and Its Applications, Aligarh (Indie), 20-22 November, 2017
- Witold Jarczyk "On weighted quasi-arithmetic mean which are convex"
Topics in Complex Dynamics, Barcelona (Spain), 2-6 October, 2017
- Martin Himmel "Some properties of Cauchy quotient means"
XII International Symposium on Generalized Convexity and Monotonicity, Hajdúszoboszló (Hungary), August 27-September 2, 2017
- Dorota Głazowska "Convex means"
- Justyna Jarczyk "Convex means"
- Witold Jarczyk "Convexity in abelian semigroups"
Positivity IX, Edmonton (Canada), 17-21 July 2017
- Martin Himmel "Cauchy quotient means and their properties"
17th International Conference on Functional Equations and Inequalities, Będlewo (Poland), 9-15 July 2017
- Mariusz Sudzik "On a problem of Derfel"
55th International Symposium on Functional Equations, Chengdu (China), 11-18 June 2017
- Dorota Głazowska "Subcommutativity of integral quasi-arithmetic means on measure spaces"
- Martin Himmel "Some properties of Cauchy quotient means"
- Justyna Jarczyk "Joining means by iteration"
- Witold Jarczyk "Embeddability of pairs of weighted quasi-arithmetic means in a semiflow"
- Janusz Matkowski
Progress on Difference Equations 2017, Urbino (Italy), 29-31 May 2017
- Dorota Głazowska "Embeddability of pairs of weighted quasi-arithmetic means in a semiflow"
- Justyna Jarczyk "Embeddability of pairs of weighted quasi-arithmetic means in a semiflow"
- Witold Jarczyk "Iterated procedure of joining means"
- Mariusz Sudzik "On a problem of Derfel"
2016
21st European Conference on Iteration Theory, Innsbruck (Austria), 4-10 September 2016
- Dorota Głazowska "Iterative roots of some mean-type mappings"
- Justyna Jarczyk "Iterated joining means"
- Witold Jarczyk "On a linear iterative functional equation with commuting given functions"
- Janusz Matkowski "Beta-type functions and means"
Conference on Inequalities and Applications, Hajdúszoboszló (Hungary), August 28 - September 3, 2016
- Witold Jarczyk "Convex functions in abelian semigroup setting"
- Janusz Matkowski "On some applications of a sandwich theorem"
54th International Symposium on Functional Equations, Hajdúszoboszló (Hungary), 12-19 June 2016
- Dorota Głazowska "Regularity theorem for a problem of the invariance in the class of Lagrange means"
- Martin Himmel "Beta-type functions and means"
- Justyna Jarczyk "Joining means"
- Witold Jarczyk "On some properties of strictly convex functions"
- Janusz Matkowski
- Tomasz Małolepszy "On the translativity of beta-type functions"
Progress on Difference Equations 2016, Riga (Latvia), 17-20 May 2016
- Dorota Głazowska "Flows of homographies"
- Justyna Jarczyk "Fractional Iterates of Piecewise Monotonic Functions of Nonmonotonicity Height Not Less than 2 – Part II"
- Witold Jarczyk "Fractional Iterates of Piecewise Monotonic Functions of Nonmonotonicity Height Not Less than 2 – Part I"
2015
Mathematical Inequalities and Applications 2015, Mostar (Bosnia and Herzegovina), 11-15 November, 2015
- Witold Jarczyk "On some properties of strictly convex functions"
Function Spaces XI, Zielona Góra (Poland), 6-10 July 2015
- Dorota Głazowska "Uniformly bounded composition operators in the Banach space of absolutely continuous functions"
- Martin Himmel "Directional convexity and characterizations of Beta and Gamma functions"
- Justyna Jarczyk "Uniform convexity of paranormed generalizations of L^p spaces"
- Janusz Matkowski "Paranormed generalizations of L^p spaces"
2nd International Conference on New Trends of Differential Equations in Sciences, Sofia (Bulgaria), 6-10 July 2015
- Tomasz Małolepszy "Some results from the theory of blow-up solution to a certain class of Volterra integral equation"
53rd International Symposium on Functional Equations, Krynica-Zdrój (Poland), 14-21 June 2015
- Dorota Głazowska "Subcommuting and commuting real homographic functions"
- Justyna Jarczyk "On marginal joints of means"
- Witold Jarczyk "Convexity in an abelian semigroup setting"
- Janusz Matkowski "Commutativity of integral quasi-arithmetic means on probability spaces"
20th International Conference on Mathematical Modelling and Analysis, Sigulda (Latvia), 26-29 May 2015
- Tomasz Małolepszy "Blow-up solutions to a certain class of Volterra integral equations"
16th International Conference on Functional Equations and Inequalities, Będlewo (Poland), 17-23 May 2015
- Dorota Głazowska "Subcommuting real homographic functions"
- Matrin Himmel
- Justyna Jarczyk "Around a problem of Zoltán Daróczy"
- Witold Jarczyk "On some properties of strictly convex functions"
- Tomasz Małolepszy "The application of the Schröder equation in the theory of blow-up solutions for Volterra integral equations"
- Janusz Matkowski "Directional convexity and characterizations of Beta and Gamma functions"
2014
20th European Conference on Iteration Theory, Łagów (Poland), 14-20 September 2014
- Dorota Głazowska "Commuting real homographic functions"
- Justyna Jarczyk "Parametrized means and their Gauss compositions"
- Witold Jarczyk "Iterative roots of piecewise monotonic functions of nonmonotonicity height not less than 2 revisited"
- Dorota Krassowska "Embeddability of homeomorphisms of the circle in set-valued iteration groups"
- Janusz Matkowski "Homographic commuting functions"
- Łukasz Sadowski "Takagi function as a unique solution of some functional equations"
IX Forum Równań Różniczkowych Cząstkowych, Będlewo (Poland), 1-5 September 2014
- Tomasz Małolepszy "Szacowanie czasu wybuchu rozwiązań dla pewnej klasy równań całkowych Volterry - podejście "całkowe""
XI International Symposium on Generalized Convexity and Monotonicity, Rio de Janeiro, (Brazil), 25-29 August 2014
- Justyna Jarczyk "Uniform convexity of paranormed generalizations of L^p spaces"
- Witold Jarczyk "Convexity and a Stone-type theorem for convex sets in Abelian semigroup setting"
52nd International Symposium on Functional Equations, Innsbruck (Austria), 22-29 June 2014
- Dorota Głazowska "Invariance equation involving Matkowski means"
- Justyna Jarczyk "Parametrized means and their Gauss compositions"
- Witold Jarczyk "Convexity on groups" survey talk
- Janusz Matkowski "Invariance formulas for weighted quasi-arithmetic means of bounded sequences"
2013
Numbers, Functions, Equations 2013 (NFE'13), Visegrád (Hungary), 28-30 June 2013
- Dorota Głazowska "Invariance of the quasi-arithmetic mean in the class of generalized weighted quasi-arithmetic means"
- Justyna Jarczyk "Conditional homogenity and translativity of Makó-Páles means"
- Witold Jarczyk "Uniqueness of solutions of simultaneous difference equations"
- Janusz Matkowski "Invariance formula for generalized quasi-arithmetic means"
51st International Symposium on Functional Equations, Rzeszów (Poland), 16-23 June 2013
- Justyna Jarczyk "Uniform convexity of finite dimensional paranormed spaces"
- Witold Jarczyk "On some functional equations stemming from probability theory"
- Janusz Matkowski "Continuity of monotonic and homogeneous functions of several variables"
15th International Conference on Functional Equations and Inequalities, Ustroń (Poland), 19-25 May 2013
- Dorota Głazowska "Invariance equation involving quasi-arithmetic mean and Matkowski means"
- Hideaki Izumi "Formal series solutions of iterative functional equations"
- Justyna Jarczyk "Uniform convexity of paranormed generalizations of L^p spaces"
- Witold Jarczyk "Iterative roots of piecewise monotonic functions revisited"
- Tomasz Małolepszy "Schröder equation and the existence of the blow-up solutions of some class of Volterra integral equations"
- Janusz Matkowski "Continuity of means and uniqueness of invariant means"
2012
European Conference on Iteration Theory, Ponta Delgada (Azory, Portugalia), 9-15 September 2012
- Justyna Jarczyk "The convergence of iterates of random mean-type mappings"
- Witold Jarczyk "Recent results on iterative roots" survey talk
- Dorota Krassowska "On the embeddability of continuous mappings In shorten iteration semigroups"
- Janusz Matkowski "Iterations of pre-mean-type mappings"
XLI Polish Conference of Applied Mathematics, Zakopane-Kościelisko (Polska), 4 - 11 September, 2012
- Tomasz Małolepszy "The analysis of the existence of blow-up solutions in some model of superdiffusion"
50th International Symposium on Functional Equations, Hajdúszoboszló (Węgry), 17-24 June 2012
- Justyna Jarczyk "Random means"
- Witold Jarczyk "Improving regularity of solutions of difference equation"
- Janusz Matkowski "Convergence of iterates of pre-mean-type mapping"
VIII Forum on Partial Differential Equations, Będlewo (Polska), 17 - 22 June 2012
- Tomasz Małolepszy "Blow-up solutions in diffusion models"
2011
14th International Conference on Functional Equations and Inequalities, Będlewo (Poland), 11-17 September 2011
- Dorota Głazowska "Uniformly bounded composition operators in the space of functions of bounded $\varphi$-variation with weight in the sense of Riesz"
- Justyna Jarczyk "On some equality problem connected with conjugate means"
- Witold Jarczyk "Note on an equation occuring in a problem of Nicole Briouet-Belluot"
49th International Symposium on Functional Equations, Graz (Austria), 19-26 June 2011
- Justyna Jarczyk "On a functional equation connected with conjugate means"
- Witold Jarczyk "Convexity and almost convexity in Abelian groups"
- Dorota Krassowska "On conjugacy of regular iteration groups with two fixed points"
- Janusz Matkowski "Pointwise monotonicity and generalized subadditive functions"
11st Katowice-Debrecen Winter Seminar on Functional Equations and Inequalities, Wisła Malinka (Poland), 2-5 February 2011
- Janusz Matkowski "Generalized subadditive function - monotonicity and periodicity"
2010
18th European Conference on Iteration Theory, Nant (France), 12-17 September 2010
- Justyna Jarczyk "Iterative roots of piecewise monotonic functions of nonmonotonicity height not less than 2, part II"
- Witold Jarczyk "Iterative roots of piecewise monotonic functions of nonmonotonicity height not less than 2, part I"
- Dorota Krassowska "On C^1 iteration groups with two fixed points"
- Janusz Matkowski "Mean-type mappings and invariant curves"
48th International Symposium on Functional Equations, Batz-sur-Mer (France), 13-18 June 2010
- Justyna Jarczyk "On an equation involving weighted quasi-arithmetic means"
- Witold Jarczyk "On a functional equation in probability theory"
- Janusz Matkowski
2009
9th Katowice-Debrecen Winter Seminar on Functional Equations and Inequalities, Będlewo (Poland), 4-7 February 2009
- Janusz Matkowski "On composition operators"
13th International Conference on Functional Equations and Inequalities, Małe Ciche (Poland), 13-19 September 2009
- Dorota Głazowska "An invariance of the geometric mean with respect to the Cauchy mean-type mappings"
- Dorota Krassowska "On iteration semigroups containing generalized convex and concave functions"
2008
8th Debrecen-Katowice Winter Seminar on Functional Equations and Inequalities, Poroszló (Hungary), 30 January- 2 February 2008
- Janusz Matkowski "A converse of Hölder inequality theorem"
Numbers, Functions, Equations, 08, Noszvaj (Hungary),15-21 June 2008
- Justyna Jarczyk "Regularity theorem for a functional equation involving means"
- Witold Jarczyk "Convex functions and almost convex functions on Abelian groups"
- Janusz Matkowski "On invariant means"
46th International Symposium on Functional Equations, Opava (Czech Republic), 22-29 June 2008
- Justyna Jarczyk "On an equation involving weighted quasi-arithmetic means with continuous generators"
- Witold Jarczyk "Iterative roots of mappings with a unique set-value point"
- Dorota Krassowska "On the embeddability of commuting continuous injections in an iteration semigroup"
- Janusz Matkowski "Invariance of means with two generators with respect to some one-generator means"
12th International Conference on Functional Equations and Inequalities, Będlewo (Poland), 7-13 September 2008
- Dorota Głazowska "An invariance of the geometric mean in the class of Cauchy means"
- Justyna Jarczyk "On an equation involving weighted quasi-arithmetic means"
- Witold Jarczyk "Iterability in a class of mean-type mappings"
17th European Conference on Iteration Theory, Jałta (Ukraine), 7-13 September 2008
- Dorota Krassowska "On iteration groups containing generalized convex and concave functions"
- Janusz Matkowski "Iterations of the mean-type mappings"
2007
7th Katowice-Debrecen Winter Seminar on Functional Equations and Inequalities, Będlewo (Poland), 31 January-3 February 2007
- Janusz Matkowski "On a generalization of Lagrange and Cauchy mean-value theorems"
45th International Symposium on Functional Equations, Bielsko-Biała (Poland), 24 June -1 July 2007
- Justyna Jarczyk "Invariance in the class of Bajraktarević means"
- Witold Jarczyk "Convexity and almost convexity on Abelian groups"
- Witold Jarczyk "On stability of random variables via functional equations"
- Dorota Krassowska "On simultaneous Abel's functional inequalities"
- Janusz Matkowski "Jensen functional equation and uniformly continuous Nemytskii operators"
Conference on Inequalities and Applications '07, Noszvaj (Hungary), 9-15 September 2007
- Janusz Matkowski "Uniformly continuous Nemytskii operators in some function spaces"
2006
6th Debrecen-Katowice Winter Seminar on Functional Equations and Inequalities, Berekfürdő (Hungary), 1-4 February, 2006
- Janusz Matkowski "On a generalized Gołąb-Schinzel equation"
11th International Conference on Functional Equations and Inequalities, Będlewo (Poland), 17-23 September 2006
- Dorota Głazowska "An invariance of geometric mean with respect to Lagrangean means"
- Justyna Jarczyk "Invariance in the class of quasi-arithmetic means with function weights"
- Witold Jarczyk "Almost convex functions on Abelian groups"
- Dorota Krassowska "On a nonlinear simultaneous system of functional inequalities"
- Janusz Matkowski "On extension of solutions of simultaneous systems of functional equations"
44th International Symposium on Functional Equations, May 2006, Louisville KY (USA)
- Witold Jarczyk "On a problem of N. Brillouët-Belluot"
- Janusz Matkowski "Simultaneous system of functional equations and commuting functions"
16th European Conference on Iteration Theory, Gargnano (Italy), 10-16 September 2006
- Witold Jarczyk "Continuity of semiflows"
- Dorota Krassowska "Iteration groups and commuting functions in the space R^n"
- Janusz Matkowski "Simultaneous system of functional equations and commuting functions"
The 30th Anniversary of Postgrado of Mathematics, Caracas (Wenezuela), 23-29 October 2006
- Janusz Matkowski "On Lipschitzian Nemytskii operators"
- Janusz Matkowski "Iteration of means"
2005
10th International Conference on Functional Equations and Inequalities, Będlewo (Poland), 11-17 September 2005
- Dorota Głazowska "Invariance of the geometric mean with respect to Lagrangean conditionally homogeneous mean-type mappings"
- Justyna Jarczyk "Invariance in the class of weighted quasi-arithmetic means with continuous generators"
- Witold Jarczyk "Convexity on Abelian groups"
- Dorota Krassowska "On a system of functional inequalities of iterative type"
- Janusz Matkowski "On a generalized Gołąb-Schinzel functional equation"
43th International Symposium on Functional Equations, Batz-sur-Mer (France), May 2005
- Dorota Krassowska "A pair of functional inequalities of iterative type characterizing polynomials"
- Witold Jarczyk "Also set-valued functions do not like iterative roots"
- Janusz Matkowski "On generalized Jensen functions"
2004
15th European Conference on Iteration Theory, Batschuns (Austria), 29 August - 04 September 2004
- Witold Jarczyk "On continuity of solutions to some equations of iteration theory"
- Janusz Matkowski
42th International Symposium on Functional Equations, Opava (Czech Republic), 20-27 June 2004
- Dorota Krassowska "A system of functional inequalities of iterative type and a characterization of affine functions in R^n"
- Witold Jarczyk "Non-negative solutions of some linear iterative equations, part I"
- Janusz Matkowski "Embedding of Cauchy mean into family of weighted means"