cp's OEIS Frontend

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.

A187650 Alternated cumulative sums of the (signless) central Stirling numbers of the first kind (A187646).

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%I A187650 #14 Oct 19 2024 08:33:12
%S A187650 1,0,11,214,6555,262770,13076765,777866388,53853263165,4254252038764,
%T A187650 377667803463431,37222867283396314,4033161189724173207,
%U A187650 476511397553009371918,60969023704806106263737,8398605422371512041566888
%N A187650 Alternated cumulative sums of the (signless) central Stirling numbers of the first kind (A187646).
%F A187650 a(n) = Sum_{k=0..n} (-1)^(n-k)*s(2*k,k).
%F A187650 a(n) ~ 2^(3*n-1) * c^(2*n) * n^(n - 1/2) / (sqrt(Pi*(c-1)) * (2*c-1)^n * exp(n)), where c = -LambertW(-1,-exp(-1/2)/2) = 1.7564312086261696769827376166... - _Vaclav Kotesovec_, Jul 05 2021
%p A187650 seq(sum((-1)^(n-k)*abs(combinat[stirling1](2*k,k)),k=0..n),n=0..12);
%t A187650 Table[Sum[(-1)^(n-k)Abs[StirlingS1[2k, k]], {k, 0, n}], {n, 0, 15}]
%o A187650 (Maxima) makelist(sum((-1)^(n-k)*abs(stirling1(2*k,k)),k,0,n),n,0,12);
%Y A187650 Cf. A187646, A332928.
%K A187650 nonn,easy
%O A187650 0,3
%A A187650 _Emanuele Munarini_, Mar 12 2011