Abstract:
In the present paper we will consider the generalization of some methods for evaluation of irrationality measures for γd=√dln√d+1√d−1 and currently known results overview.
The extent of irrationality for various values of Gauss hypergeometric function were estimated repeatedly, in particular for 2F(1,12,32;1d)=√dln√d+1√d−1.
The first such estimates in some special cases were obtained by D. Rhinn [1], M. Huttner [2], D. Dubitskas [3]. Afterward by K. Vaananen, A. Heimonen and D. Matala-Aho [4] was elaborated the general method, which one made it possible to get upper bounds for irrationality measures of the Gauss hypergeometric function values
F(1,1k,1+1k;rs),k∈N,k⩾2,rs∈Q,(r,s)=1,rs∈(−1,1). This method used the Jacobi type polynomials to construct rational approach to the hypergeometric function.
In [4] have been obtained many certain estimates, and some of them have not been improved till now.
But for the special classes of the values of hypergeometric function later were elaborated especial methods, which allowed to get better evaluations. In the papers [5], [6] authors, worked under supervision of V. Kh. Salikhov, obtained better estimates
for the extent of irrationality for some specific values γd. In the basis of proofs for that results were lying symmetrized integral constructions.
It should be remarked, that lately symmetrized integrals uses very broadly for researching of irrationality measures. By using such integrals
were obtained new estimates for
ln2 ([7]), ln3, lnπ, ([8], [9]) and other values.
Here we present research and compare some of such symmetrized constructions, which earlier
allowed to improve upper bounds of irrationality measure for specific values of γd.
This work is devoted to the seventieth Doctor of Physical and Mathematical Sciences, Professor Vasily Ivanovich Bernik. In her curriculum vitae, a brief analysis of his scientific work and educational and organizational activities. The work included a list of 80 major scientific
works of V. I. Bernik.
Bibliography: 17 titles.
\Bibitem{BasZol17}
\by M.~G.~Bashmakova, E.~S.~Zolotukhina
\paper On irrationality measure
of the numbers $\sqrt{d}\ln{\frac{\sqrt{d}+1}{\sqrt{d}-1}}$
\jour Chebyshevskii Sb.
\yr 2017
\vol 18
\issue 1
\pages 29--43
\mathnet{http://mi.mathnet.ru/cheb531}
\crossref{https://doi.org/10.22405/2226-8383-2017-18-1-29-43}
\elib{https://elibrary.ru/item.asp?id=29119834}
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This publication is cited in the following 3 articles:
M. G. Bashmakova, N. V. Sycheva, “O nekotorykh metodakh otsenki pokazatelya irratsionalnosti znachenii funktsii arctanx”, Chebyshevskii sb., 25:1 (2024), 5–15
A. V. Begunts, “On the Convergence of Alternating Series Associated with Beatty Sequences”, Math. Notes, 107:2 (2020), 345–349
M. G. Bashmakova, E. S. Zolotukhina, “Ob otsenke mery irratsionalnosti chisel vida √4k+3ln√4k+3+1√4k+3−1 i 1√karctg1√k”, Chebyshevskii sb., 19:2 (2018), 15–29