A187648 Partial sums of the (signless) central Stirling numbers of the first kind.

1, 2, 13, 238, 7007, 276332, 13615867, 804559020, 55435688573, 4363540990502, 386285596492697, 37986820683352442, 4108370877690921963, 484652929620424467088, 61930188031979540102743, 8521504634108297687933368

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..250

Formula

a(n) = Sum_{k=0..n} A132393(2*k,k).

a(n) ~ n^n * c^(2*n) * 2^(3*n-1) / (sqrt(Pi*(c-1)*n) * exp(n) * (2*c-1)^n), where c = -LambertW(-1,-exp(-1/2)/2). - Vaclav Kotesovec, May 21 2014

Maple

seq(add(abs(combinat[stirling1](2*k, k)), k=0..n), n=0..15);

Mathematica

Flatten[Table[Sum[Abs[StirlingS1[2k, k]], {k, 0, n}], {n, 0, 15}], 1]

Prog

(Maxima) makelist(sum(abs(stirling1(2*k, k)), k, 0, n), n, 0, 12);

Crossrefs

Cf. A132393.

Sequence in context: A268703 A373871 A369799 * A113098 A365590 A135870

Adjacent sequences: A187645 A187646 A187647 * A187649 A187650 A187651

Keyword

nonn,easy

Author

Emanuele Munarini, Mar 12 2011

Status

approved