This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A289381 #39 May 25 2022 09:09:45
%S A289381 1,4,7,148,1333,4888,190633,2859496,1246447,923617228,19395961789,
%T A289381 11438644132,1013879820791,301122306774928,171226409734763,
%U A289381 270708953790660304,525493851475987649,104222947209404217052,11568747140243868092773,451181138469510855618148
%N A289381 a(n) = numerator of Sum_{k=1..n} 1/(2*k-1)!!.
%H A289381 Seiichi Manyama, <a href="/A289381/b289381.txt">Table of n, a(n) for n = 1..404</a>
%H A289381 OEIS Wiki, <a href="/wiki/A_remarkable_formula_of_Ramanujan">A remarkable formula of Ramanujan</a>
%F A289381 Numerators of coefficients in expansion of sqrt(Pi*x*exp(x)/2) * erf(sqrt(x/2)) / (1 - x). - _Ilya Gutkovskiy_, May 24 2022
%e A289381 1, 4/3, 7/5, 148/105, 1333/945, 4888/3465, 190633/135135, 2859496/2027025, 1246447/883575, 923617228/654729075, 19395961789/13749310575, 11438644132/8108567775, ... = a(n)/A289488(n) -> A060196.
%Y A289381 Cf. A001147, A060196, A289488, A354298.
%K A289381 nonn,frac
%O A289381 1,2
%A A289381 _Seiichi Manyama_, Sep 02 2017