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.

A187652 Alternated binomial cumulative sums of the (signless) central Stirling numbers of the first kind (A187646).

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%I A187652 #17 May 25 2025 10:11:24
%S A187652 1,0,10,194,5932,237624,11820780,702992968,48662470640,3843811669088,
%T A187652 341207224961856,33627579102171680,3643463136559851440,
%U A187652 430456189350273371648,55075003474909952394848,7586546772496980353804704
%N A187652 Alternated binomial cumulative sums of the (signless) central Stirling numbers of the first kind (A187646).
%F A187652 a(n) = Sum_{k=0..n} (-1)^(n-k)*binomial(n,k)*abs(Stirling1(2*k,k)).
%F A187652 a(n) ~ c * d^n * (n-1)!, where d = 8*w^2/(2*w-1), where w = -LambertW(-1,-exp(-1/2)/2) = 1.7564312086261696769827376166... and c = exp((1-2*w)/(8*w^2)) / (2^(3/2)*Pi*sqrt(w-1)) = exp(-1/d) / (2^(3/2)*Pi*sqrt(w-1)) = 0.11686978539934159049334861225275481804523808136863346883911376048... - _Vaclav Kotesovec_, Jul 05 2021, updated May 25 2025
%p A187652 seq(sum((-1)^(n-k)*binomial(n,k)*abs(combinat[stirling1](2*k,k)),k=0..n),n=0..12);
%t A187652 Table[Sum[(-1)^(n - k)Binomial[n, k]Abs[StirlingS1[2k, k]], {k, 0, n}], {n, 0, 15}]
%o A187652 (Maxima) makelist(sum((-1)^(n-k)*binomial(n,k)*abs(stirling1(2*k,k)),k,0,n),n,0,12);
%Y A187652 Cf. A187646.
%K A187652 nonn,easy
%O A187652 0,3
%A A187652 _Emanuele Munarini_, Mar 12 2011