Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya: Latest issue http://www.mathnet.ru/eng/im 2026, Volume 90, Issue Issue 4 en-gb Copyright 2026, Russian Academy of Sciences, Steklov Mathematical Institute of RAS Fri, 04 Sep 2026 00:00:00 +0300 math-net2026_09@mi-ras.ru tche@mi-ras.ru Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya http://www.mathnet.ru/JrnLogos/im/im_e.svg http://www.mathnet.ru/eng/im Normal forms for ordinary differential operators. I Junhu Guo, A. B. Zheglov Izv. RAN. Ser. Mat., 2026, 90:4, 3--50 http://mi.mathnet.ru/eng/im9625 Thu, 23 Jul 2026 00:00:00 +0300 Tue, 01 Sep 2026 00:00:00 +0300 http://mi.mathnet.ru/eng/im9625 On the positivity of direct image bundles. II Zhi Li, Wang Xu, Xiangyu Zhou Izv. RAN. Ser. Mat., 2026, 90:4, 51--70 http://mi.mathnet.ru/eng/im9710 Thu, 23 Jul 2026 00:00:00 +0300 Tue, 01 Sep 2026 00:00:00 +0300 http://mi.mathnet.ru/eng/im9710 Asymptotic behavior of period lengths of continued fractions in a hyperelliptic field V. P. Platonov, G. V. Fedorov Izv. RAN. Ser. Mat., 2026, 90:4, 71--104 http://mi.mathnet.ru/eng/im9740 Thu, 23 Jul 2026 00:00:00 +0300 Fri, 04 Sep 2026 00:00:00 +0300 http://mi.mathnet.ru/eng/im9740 On the complexity of first-order logics of probability S. O. Speranski, A. V. Grefenshtein Izv. RAN. Ser. Mat., 2026, 90:4, 105--126 http://mi.mathnet.ru/eng/im9718 Thu, 23 Jul 2026 00:00:00 +0300 Fri, 04 Sep 2026 00:00:00 +0300 http://mi.mathnet.ru/eng/im9718 Solvability of the Cauchy problem for a system of non-linear parabolic equations A. Kh. Khachatryan, Kh. A. Khachatryan, H. S. Petrosyan Izv. RAN. Ser. Mat., 2026, 90:4, 127--148 http://mi.mathnet.ru/eng/im9705 Thu, 23 Jul 2026 00:00:00 +0300 Tue, 01 Sep 2026 00:00:00 +0300 http://mi.mathnet.ru/eng/im9705 On Hollenbeck--Verbitsky conjecture for $4/3\lt p\lt 2$ and reverse Riesz-type inequalities for $2\lt p\lt 4$ V. Jaguzović Izv. RAN. Ser. Mat., 2026, 90:4, 149--165 http://mi.mathnet.ru/eng/im9742 Thu, 23 Jul 2026 00:00:00 +0300 Tue, 01 Sep 2026 00:00:00 +0300 http://mi.mathnet.ru/eng/im9742 On two families of Nekrasov--Okounkov type formulas Chenglang Yang Izv. RAN. Ser. Mat., 2026, 90:4, 166--194 http://mi.mathnet.ru/eng/im9741 Thu, 23 Jul 2026 00:00:00 +0300 Thu, 03 Sep 2026 00:00:00 +0300 http://mi.mathnet.ru/eng/im9741 On periodic $E$-functions A. Ya. Yanchenko Izv. RAN. Ser. Mat., 2026, 90:4, 195--204 http://mi.mathnet.ru/eng/im9744 Thu, 23 Jul 2026 00:00:00 +0300 Thu, 03 Sep 2026 00:00:00 +0300 http://mi.mathnet.ru/eng/im9744