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

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