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A187664 Convolution of the (signless) central Lah numbers (A187535) and the (signless) central Stirling numbers of the first kind (A187646). 0
1, 3, 49, 1483, 67615, 4173203, 326208269, 30880075203, 3430574739759, 437145190334383, 62803806114813801, 10038354053796477099, 1766255133182030548351, 339166069936077378326187, 70571377417819411767223541 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..14.

FORMULA

a(n) = sum(Lah(2k,k)s(2n-2k,n-k)),k=0..n)

MAPLE

L := n -> if n=0 then 1 else binomial(2*n-1, n-1)*(2*n)!/n! fi;

seq(sum(L(k)*abs(combinat[stirling1](2*(n-k), n-k)), k=0..n), n=0..12);

MATHEMATICA

L[n_] := If[n == 0, 1, Binomial[2n - 1, n - 1](2n)!/n!]

Table[Sum[L[k]Abs[StirlingS1[2n - 2k, n - k]], {k, 0, n}], {n, 0, 14}]

PROG

(Maxima) L(n):= if n=0 then 1 else binomial(2*n-1, n-1)*(2*n)!/n!;

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

CROSSREFS

Cf. A187535, A187646

Sequence in context: A173174 A302466 A303248 * A336673 A012199 A337154

Adjacent sequences:  A187661 A187662 A187663 * A187665 A187666 A187667

KEYWORD

nonn,easy

AUTHOR

Emanuele Munarini, Mar 12 2011

STATUS

approved

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Last modified January 26 22:05 EST 2022. Contains 350601 sequences. (Running on oeis4.)