A192569 - OEIS

A192569

Unsigned sum of a triple diagonal product of Stirling numbers of the first kind.

1, 1, 19, 951, 101126, 19471950, 6120757875, 2923391598085, 2012458144311874, 1917251981582592942, 2447403154245760930044, 4077096587506331113785984, 8671231633412537292307441446, 23111533287530979373465097259402

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OFFSET

0,3

LINKS

Table of n, a(n) for n=0..13.

FORMULA

a(n) = sum(abs(stirling1(n,k)*stirling1(n+1,k+1)*stirling1(n+2,k+2)),k=0..n).

MATHEMATICA

Table[Sum[Abs[StirlingS1[n, k]StirlingS1[n+1, k+1]StirlingS1[n+2, k+2]], {k, 0, n}], {n, 0, 100}]

PROG

(Maxima) makelist(sum(abs(stirling1(n, k)*stirling1(n+1, k+1)*stirling1(n+2, k+2)), k, 0, n), n, 0, 24);

CROSSREFS

Sequence in context: A005535 A171226 A247279 * A238740 A285862 A136022

Adjacent sequences: A192566 A192567 A192568 * A192570 A192571 A192572

KEYWORD

nonn

AUTHOR

Emanuele Munarini, Jul 04 2011

STATUS

approved