A187650 Alternated cumulative sums of the (signless) central Stirling numbers of the first kind (A187646).
1, 0, 11, 214, 6555, 262770, 13076765, 777866388, 53853263165, 4254252038764, 377667803463431, 37222867283396314, 4033161189724173207, 476511397553009371918, 60969023704806106263737, 8398605422371512041566888
Offset: 0
Programs
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Maple
seq(sum((-1)^(n-k)*abs(combinat[stirling1](2*k,k)),k=0..n),n=0..12);
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Mathematica
Table[Sum[(-1)^(n-k)Abs[StirlingS1[2k, k]], {k, 0, n}], {n, 0, 15}]
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Maxima
makelist(sum((-1)^(n-k)*abs(stirling1(2*k,k)),k,0,n),n,0,12);
Formula
a(n) = Sum_{k=0..n} (-1)^(n-k)*s(2*k,k).
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