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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.

A187651 Alternated binomial partial sums of the central Stirling numbers of the second kind.

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%I A187651 #23 Oct 19 2024 08:33:16
%S A187651 1,0,6,71,1380,34854,1092317,40900215,1781924888,88569337730,
%T A187651 4946558473226,306691008191732,20903038895529727,1553426761730508586,
%U A187651 125016067017985968931,10831572432055401760624,1005245087722396707881648
%N A187651 Alternated binomial partial sums of the central Stirling numbers of the second kind.
%F A187651 a(n) = Sum_{k=0..n} (-1)^(n-k)*binomial(n,k)*S(2*k,k).
%F A187651 a(n) ~ c * d^n * (n-1)!, where d = 4/(w*(2-w)) = 6.176554609483480358231680164... and c = exp(w^2/4 - 1) / (Pi * sqrt(2*w * (1-w))) = 0.17569156962762991098958896633434384684339835018075095823375851..., where w = -LambertW(-2*exp(-2))^2 = -A226775. - _Vaclav Kotesovec_, Mar 30 2018, updated Jul 07 2021
%p A187651 seq(add((-1)^(n-k)*binomial(n,k)*combinat[stirling2](2*k,k), k=0..n), n=0..20);
%t A187651 Table[Sum[(-1)^(n-k)Binomial[n, k] StirlingS2[2k, k], {k, 0, n}], {n, 0, 16}]
%o A187651 (Maxima) makelist(sum((-1)^(n-k) *binomial(n,k) *stirling2(2*k,k), k,0,n), n,0,12);
%Y A187651 Cf. A187653.
%K A187651 nonn,easy
%O A187651 0,3
%A A187651 _Emanuele Munarini_, Mar 12 2011