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A187658
Binomial convolution of the (signless) central Stirling numbers of the first kind (A187646).
0
1, 2, 24, 516, 16064, 655840, 33157240, 1999679696, 140128848384, 11189643689088, 1003005057594240, 99725721676986240, 10892178742891589792, 1296379044138734510656, 166999512859041432577280, 23149972436862049305233280
OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} binomial(n,k)*s(2*k,k)*s(2*n-2*k,n-k).
MAPLE
seq(sum(binomial(n, k)*abs(combinat[stirling1](2*k, k))*abs(combinat[stirling1](2*(n-k), n-k)), k=0..n), n=0..12);
MATHEMATICA
Table[Sum[Binomial[n, k]Abs[StirlingS1[2k, k]]Abs[StirlingS1[2n - 2k, n - k]], {k, 0, n}], {n, 0, 15}]
PROG
(Maxima) makelist(sum(binomial(n, k)*abs(stirling1(2*k, k))*abs(stirling1(2*n-2*k, n-k)), k, 0, n), n, 0, 12);
CROSSREFS
Cf. A187646.
Sequence in context: A012236 A186414 A359848 * A138450 A262009 A367271
KEYWORD
nonn,easy
AUTHOR
Emanuele Munarini, Mar 12 2011
STATUS
approved