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A091530 Sum {k=1 to n} H(k) k! (n-k)!, where H(k) is the k-th harmonic number. 1
1, 4, 16, 73, 388, 2396, 17024, 137544, 1248816, 12603288, 140018688, 1698063552, 22318009344, 315942698880, 4791898275840, 77510315197440, 1331759355586560, 24220225133061120, 464796175236710400, 9385769913543475200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..20.

MATHEMATICA

Table[ Sum[ HarmonicNumber[k]k!(n - k)!, {k, 1, n}], {n, 1, 20}] (* Robert G. Wilson v, Jan 14 2004 *)

CROSSREFS

Cf. A091528.

Sequence in context: A007234 A096244 A030131 * A301455 A214372 A109957

Adjacent sequences:  A091527 A091528 A091529 * A091531 A091532 A091533

KEYWORD

nonn

AUTHOR

Leroy Quet, Jan 08 2004

EXTENSIONS

Extended by Robert G. Wilson v, Jan 14 2004

STATUS

approved

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Last modified December 15 11:43 EST 2019. Contains 329999 sequences. (Running on oeis4.)