A026025 a(n) = (n!)^2 * (1 + Sum(k=0...n-1) 1/((k+1)(k!)^2)).

1, 2, 10, 93, 1492, 37305, 1342986, 65806321, 4211604552, 341139968721, 34113996872110, 4127793621525321, 594402281499646236, 100453985573440213897, 19688981172394281923826

Offset

0,2

Links

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

Formula

a(n) = n^2*a(n-1)+n. - Vladeta Jovovic, Apr 13 2003

Crossrefs

Sequence in context: A260339 A205320 A254243 * A231375 A100622 A355782

Adjacent sequences: A026022 A026023 A026024 * A026026 A026027 A026028

Keyword

easy,nonn

Author

Brian Wallace (wallacebrianedward(AT)yahoo.co.uk), May 18 2001

Extensions

Corrected and extended by Matthew Conroy, May 22 2001

Status

approved