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 A386274 #16 Aug 01 2025 15:41:58
%S A386274 1,35,1470,65170,2965235,136993857,6393046660,300473193020,
%T A386274 14197358370195,673585780452585,32062683149543046,1530264423046372650,
%U A386274 73197648235718158425,3507856526988647130675,168377113295455062272400,8093326579068206659893360,389491341617657445507367950
%N A386274 Expansion of 1/(1 - 49*x)^(5/7).
%H A386274 Harvey P. Dale, <a href="/A386274/b386274.txt">Table of n, a(n) for n = 0..592</a>
%F A386274 a(n) = (-49)^n * binomial(-5/7,n).
%F A386274 a(n) = 7^n/n! * Product_{k=0..n-1} (7*k+5).
%F A386274 a(n) = 7^n * Product_{k=1..n} (7 - 2/k).
%F A386274 D-finite with recurrence n*a(n) +7*(-7*n+2)*a(n-1)=0. - _R. J. Mathar_, Jul 30 2025
%t A386274 CoefficientList[Series[1/(Surd[1-49x,7])^5,{x,0,20}],x] (* _Harvey P. Dale_, Aug 01 2025 *)
%o A386274 (PARI) my(N=20, x='x+O('x^N)); Vec(1/(1-49*x)^(5/7))
%Y A386274 Cf. A034835, A216703, A386271, A386272, A386273.
%K A386274 nonn,easy
%O A386274 0,2
%A A386274 _Seiichi Manyama_, Jul 17 2025