Kubiak, Mateusz; Szal, Bogdan A sufficient condition for uniform convergence of trigonometric series with \(p\)-bounded variation coefficients. (English) Zbl 1526.42006 Result. Math. 78, No. 6, Paper No. 236, 19 p. (2023). Reviewer: Xhevat Z. Krasniqi (Prishtina) MSC: 42A20 42A32 40A30 PDFBibTeX XMLCite \textit{M. Kubiak} and \textit{B. Szal}, Result. Math. 78, No. 6, Paper No. 236, 19 p. (2023; Zbl 1526.42006) Full Text: DOI arXiv OA License
Krasniqi, Xh. Z.; Kórus, P.; Szal, B. Approximation by double second type delayed arithmetic mean of periodic functions in \(H_p^{(\omega, \omega)}\) space. (English) Zbl 07687231 Bol. Soc. Mat. Mex., III. Ser. 29, No. 1, Paper No. 21, 34 p. (2023). Reviewer: Włodzimierz Łenski (Poznań) MSC: 41A25 42A10 PDFBibTeX XMLCite \textit{Xh. Z. Krasniqi} et al., Bol. Soc. Mat. Mex., III. Ser. 29, No. 1, Paper No. 21, 34 p. (2023; Zbl 07687231) Full Text: DOI arXiv
Kubiak, Mateusz; Szal, Bogdan A sufficient condition for uniform convergence of double sine series with p-bounded variation coefficients. arXiv:2305.09040 Preprint, arXiv:2305.09040 [math.CA] (2023). MSC: 42A20 42A32 40A05 40B05 BibTeX Cite \textit{M. Kubiak} and \textit{B. Szal}, ``A sufficient condition for uniform convergence of double sine series with p-bounded variation coefficients'', Preprint, arXiv:2305.09040 [math.CA] (2023) Full Text: arXiv OA License
Krasniqi, Xhevat Z.; Łenski, Włodzimierz; Szal, Bogdan Seminormed approximation by deferred matrix means of integrable functions in \(H_P^{(\omega)}\) space. (English) Zbl 07544240 Result. Math. 77, No. 4, Paper No. 145, 16 p. (2022). MSC: 40G05 41A25 42A05 42A10 PDFBibTeX XMLCite \textit{X. Z. Krasniqi} et al., Result. Math. 77, No. 4, Paper No. 145, 16 p. (2022; Zbl 07544240) Full Text: DOI
Kórus, Péter; Krasniqi, Xhevat Z.; Szal, Bogdan Uniform convergence of sine integral-series. (English) Zbl 1498.40002 Quaest. Math. 45, No. 5, 711-722 (2022). Reviewer: İsmail Aslan (Ankara) MSC: 40A10 42B10 42A38 PDFBibTeX XMLCite \textit{P. Kórus} et al., Quaest. Math. 45, No. 5, 711--722 (2022; Zbl 1498.40002) Full Text: DOI
Krasniqi, Xhevat Z.; Lenski, Włodzimierz; Szal, Bogdan Approximation by some subsequences of matrix means. (English) Zbl 1484.42007 Lith. Math. J. 62, No. 1, 28-42 (2022). MSC: 42A24 41A25 42A10 PDFBibTeX XMLCite \textit{X. Z. Krasniqi} et al., Lith. Math. J. 62, No. 1, 28--42 (2022; Zbl 1484.42007) Full Text: DOI
Kubiak, Mateusz; Szal, Bogdan A necessary condition for uniform convergence of double sine series with \(p\)-bounded variation coefficients. (English) Zbl 1495.42002 Colloq. Math. 166, No. 2, 291-312 (2021). Reviewer: Hare Krishna Nigam (Gaya) MSC: 42A20 42A32 40A05 40B05 PDFBibTeX XMLCite \textit{M. Kubiak} and \textit{B. Szal}, Colloq. Math. 166, No. 2, 291--312 (2021; Zbl 1495.42002) Full Text: DOI
Łenski, Włodzimierz; Singh, Uaday; Szal, Bogdan Trigonometric approximation of functions in seminormed spaces. (English) Zbl 1466.42003 Math. Inequal. Appl. 24, No. 1, 89-101 (2021). MSC: 42A10 40C05 41A25 42A24 46E30 PDFBibTeX XMLCite \textit{W. Łenski} et al., Math. Inequal. Appl. 24, No. 1, 89--101 (2021; Zbl 1466.42003) Full Text: DOI
Łenski, Włodzimierz; Szal, Bogdan Pointwise approximation of functions by matrix operators of their Fourier series with \(r\)-differences of the entries. (English) Zbl 1462.42007 Lith. Math. J. 60, No. 4, 494-512 (2020). MSC: 42A24 41A25 42A10 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Lith. Math. J. 60, No. 4, 494--512 (2020; Zbl 1462.42007) Full Text: DOI arXiv
Szal, Bogdan; Łenski, Włodzimierz Pointwise approximation of modified conjugate functions by matrix operators of their Fourier series with the use of some parameters. (English) Zbl 1450.42002 Tamkang J. Math. 51, No. 2, 145-159 (2020). MSC: 42A24 41A25 PDFBibTeX XMLCite \textit{B. Szal} and \textit{W. Łenski}, Tamkang J. Math. 51, No. 2, 145--159 (2020; Zbl 1450.42002) Full Text: DOI
Kubiak, Mateusz; Szal, Bogdan Uniform convergence of trigonometric series with \(p\)-bounded variation coefficients. (English) Zbl 1453.42004 Bull. Belg. Math. Soc. - Simon Stevin 27, No. 1, 89-110 (2020). Reviewer: Elijah Liflyand (Ramat-Gan) MSC: 42A20 40A30 42A10 26A48 PDFBibTeX XMLCite \textit{M. Kubiak} and \textit{B. Szal}, Bull. Belg. Math. Soc. - Simon Stevin 27, No. 1, 89--110 (2020; Zbl 1453.42004) Full Text: DOI Euclid
Łenski, Włodzimierz; Szal, Bogdan Trigonometric approximation of functions from \(L_{2\pi}^{p(x)}\). (English) Zbl 1436.42004 Result. Math. 75, No. 2, Paper No. 56, 14 p. (2020). MSC: 42A10 41A25 46E30 42A24 40C05 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Result. Math. 75, No. 2, Paper No. 56, 14 p. (2020; Zbl 1436.42004) Full Text: DOI
Szal, Bogdan; Kubiak, Maciej On weighted integrability of functions defined by trigonometric series with \(p\)-bounded variation coefficients. (English) Zbl 1499.42021 J. Inequal. Appl. 2019, Paper No. 275, 18 p. (2019). MSC: 42A16 42A20 42A32 41A50 42A10 PDFBibTeX XMLCite \textit{B. Szal} and \textit{M. Kubiak}, J. Inequal. Appl. 2019, Paper No. 275, 18 p. (2019; Zbl 1499.42021) Full Text: DOI
Krasniqi, Xhevat Z.; Szal, Bogdan On the degree of approximation of continuous functions by means of Fourier series in the Hölder metric. (English) Zbl 1474.42011 Anal. Theory Appl. 35, No. 4, 392-404 (2019). MSC: 42A10 42A24 42B05 42B08 41A25 PDFBibTeX XMLCite \textit{X. Z. Krasniqi} and \textit{B. Szal}, Anal. Theory Appl. 35, No. 4, 392--404 (2019; Zbl 1474.42011) Full Text: DOI
Duzinkiewicz, Krzysztof; Szal, Bogdan On weighted integrability of double sine series. (English) Zbl 1440.42011 J. Math. Anal. Appl. 472, No. 2, 1581-1603 (2019). MSC: 42A20 42A05 42A32 40A05 42B05 PDFBibTeX XMLCite \textit{K. Duzinkiewicz} and \textit{B. Szal}, J. Math. Anal. Appl. 472, No. 2, 1581--1603 (2019; Zbl 1440.42011) Full Text: DOI
Kubiak, Mateusz; Łenski, Włodzimierz; Szal, Bogdan Pointwise approximation of modified conjugate functions by matrix operators of conjugate Fourier series of \(2\pi /r\)-periodic functions. (English) Zbl 1497.42008 J. Inequal. Appl. 2018, Paper No. 92, 14 p. (2018). MSC: 42A24 42A10 42A20 42A50 PDFBibTeX XMLCite \textit{M. Kubiak} et al., J. Inequal. Appl. 2018, Paper No. 92, 14 p. (2018; Zbl 1497.42008) Full Text: DOI
Łenski, Włodzimierz; Szal, Bogdan On estimates of deviation of functions from matrix operators of their Fourier series by some expressions with \(r\)-differences of the entries. (English) Zbl 1470.42007 Abstr. Appl. Anal. 2016, Article ID 9712878, 10 p. (2016). MSC: 42A10 42A20 30E10 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Abstr. Appl. Anal. 2016, Article ID 9712878, 10 p. (2016; Zbl 1470.42007) Full Text: DOI arXiv
Łenski, W.; Szal, B. On pointwise approximation of functions by some matrix means of Fourier series. (English) Zbl 1334.42009 Math. Inequal. Appl. 19, No. 1, 287-296 (2016). MSC: 42A24 40C05 40G05 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Math. Inequal. Appl. 19, No. 1, 287--296 (2016; Zbl 1334.42009)
Łenski, W.; Szal, B. On pointwise approximation of functions by some matrix means of conjugate Fourier series. (English) Zbl 1339.42004 Fasc. Math. 55, 91-108 (2015). MSC: 42A10 42A24 42A50 40C05 40G05 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Fasc. Math. 55, 91--108 (2015; Zbl 1339.42004)
Łenski, Włodzimierz; Szal, Bogdan Pointwise strong approximation of almost periodic functions in \(S^{1}\). (English) Zbl 1325.42003 Math. Inequal. Appl. 18, No. 2, 735-750 (2015). MSC: 42A24 42A75 42A10 40C05 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Math. Inequal. Appl. 18, No. 2, 735--750 (2015; Zbl 1325.42003) Full Text: DOI arXiv
Łenski, Włodzimierz; Szal, Bogdan On the degree of strong approximation of integrable functions in Stepanov sense. (English) Zbl 1307.42006 Hudzik, Henryk (ed.) et al., Function spaces X. Proceedings of the 10th international conference, Poznań, Poland, July 9–13, 2012. Warszawa: Polish Academy of Sciences, Institute of Mathematics (ISBN 978-83-86806-25-6/pbk). Banach Center Publications 102, 169-179 (2014). MSC: 42A75 42A24 42A10 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Banach Cent. Publ. 102, 169--179 (2014; Zbl 1307.42006) Full Text: DOI arXiv Link
Łenski, Włodzimierz; Szal, Bogdan Applications of general monotone sequences to strong approximation by Fourier series. (English) Zbl 1297.42008 Indag. Math., New Ser. 25, No. 1, 122-130 (2014). Reviewer: László Leindler (Szeged) MSC: 42A24 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Indag. Math., New Ser. 25, No. 1, 122--130 (2014; Zbl 1297.42008) Full Text: DOI
Łenski, Włodzimierz; Szal, Bogdan Approximation of functions from \(L^p(\omega)_\beta\) by linear operators of their Fourier series. (English) Zbl 1290.42010 Commentat. Math. 51, No. 2, 189-202 (2011). MSC: 42A24 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Commentat. Math. 51, No. 2, 189--202 (2011; Zbl 1290.42010)
Szal, B. On the integral modulus of continuity of Fourier series. (English) Zbl 1274.42007 Acta Math. Hung. 131, No. 1-2, 138-159 (2011). MSC: 42A20 42A32 PDFBibTeX XMLCite \textit{B. Szal}, Acta Math. Hung. 131, No. 1--2, 138--159 (2011; Zbl 1274.42007) Full Text: DOI
Szal, Bogdan On the rate of summability by matrix means in the generalized Hölder metric. (English) Zbl 1239.42005 Nawrocki, Marek (ed.) et al., Marcinkiewicz centenary volume. Proceedings of the Józef Marcinkiewicz centenary conference, June 28–July 2, 2010. Warszawa: Polish Academy of Sciences, Institute of Mathematics (ISBN 978-83-86806-14-0/pbk). Banach Center Publications 95, 359-368 (2011). MSC: 42A24 41A25 PDFBibTeX XMLCite \textit{B. Szal}, Banach Cent. Publ. 95, 359--368 (2011; Zbl 1239.42005) Full Text: DOI
Łenski, Włodzimierz; Szal, Bogdan Approximation of functions from \(L^{p}(\omega) _{\beta }\) by general linear operators of their Fourier series. (English) Zbl 1241.42006 Nawrocki, Marek (ed.) et al., Marcinkiewicz centenary volume. Proceedings of the Józef Marcinkiewicz centenary conference, June 28–July 2, 2010. Warszawa: Polish Academy of Sciences, Institute of Mathematics (ISBN 978-83-86806-14-0/pbk). Banach Center Publications 95, 339-351 (2011). Reviewer: D. K. Ugulawa (Tbilisi) MSC: 42A24 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Banach Cent. Publ. 95, 339--351 (2011; Zbl 1241.42006) Full Text: DOI
Szal, Bogdan A new class of numerical sequences and its applications to uniform convergence of sine series. (English) Zbl 1230.40004 Math. Nachr. 284, No. 14-15, 1985-2002 (2011). MSC: 40A30 42A10 PDFBibTeX XMLCite \textit{B. Szal}, Math. Nachr. 284, No. 14--15, 1985--2002 (2011; Zbl 1230.40004) Full Text: DOI arXiv
Szal, Bogdan On \(L\)-convergence of trigonometric series. (English) Zbl 1204.42010 J. Math. Anal. Appl. 373, No. 2, 449-463 (2011). Reviewer: Miroslav Repický (Košice) MSC: 42A20 42A32 PDFBibTeX XMLCite \textit{B. Szal}, J. Math. Anal. Appl. 373, No. 2, 449--463 (2011; Zbl 1204.42010) Full Text: DOI arXiv
Szal, Bogdan Embedding relations connected with strong approximation of Fourier series. (English) Zbl 1271.42005 Proc. Indian Acad. Sci., Math. Sci. 120, No. 5, 563-582 (2010). MSC: 42A20 42A32 PDFBibTeX XMLCite \textit{B. Szal}, Proc. Indian Acad. Sci., Math. Sci. 120, No. 5, 563--582 (2010; Zbl 1271.42005) Full Text: DOI
Szal, Bogdan On weighted \(L^p\) integrability of functions defined by trigonometric series. (English) Zbl 1211.42004 J. Inequal. Appl. 2010, Article ID 485705, 19 p. (2010). Reviewer: László Losonczi (Debrecen) MSC: 42A16 42A20 PDFBibTeX XMLCite \textit{B. Szal}, J. Inequal. Appl. 2010, Article ID 485705, 19 p. (2010; Zbl 1211.42004) Full Text: DOI EuDML
Łenski, Włodzimierz; Szal, Bogdan On the degree of strong approximation of functions and conjugate functions. (English) Zbl 1207.42002 Demonstr. Math. 43, No. 1, 117-128 (2010). MSC: 42A24 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Demonstr. Math. 43, No. 1, 117--128 (2010; Zbl 1207.42002)
Łenski, Włodzimierz; Szal, Bogdan Pointwise strong and very strong approximation by matrix means of Fourier series. (English) Zbl 1172.42303 Commentat. Math. 48, No. 2, 177-198 (2008). Reviewer: László Leindler (Szeged) MSC: 42A24 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Commentat. Math. 48, No. 2, 177--198 (2008; Zbl 1172.42303)
Szal, Bogdan On the rate of strong summability by matrix means in the generalized Hölder metric. (English) Zbl 1173.42002 JIPAM, J. Inequal. Pure Appl. Math. 9, No. 1, Paper No. 28, 13 p. (2008). Reviewer: Toivo Leiger (Tartu) MSC: 42A24 41A25 42A10 PDFBibTeX XMLCite \textit{B. Szal}, JIPAM, J. Inequal. Pure Appl. Math. 9, No. 1, Paper No. 28, 13 p. (2008; Zbl 1173.42002) Full Text: EuDML EMIS
Łenski, Włodzimierz; Szal, Bogdan On the approximation of functions by matrix means in the generalized Hölder metric. (English) Zbl 1143.42003 Hudzik, Henryk (ed.) et al., Function spaces VIII. Proceedings of the 8th conference on function spaces, Bȩdlewo, Poland, July 3–7, 2006. Warsaw: Polish Academy of Sciences, Institute of Mathematics. Banach Center Publications 79, 119-129 (2008). MSC: 42A24 41A25 PDFBibTeX XMLCite \textit{W. Łenski} and \textit{B. Szal}, Banach Cent. Publ. 79, 119--129 (2008; Zbl 1143.42003) Full Text: Link