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A067710 n! sum{k|n} (sum{j=1 to k} 1/j); the k-sum is over the positive divisors, k, of n. 1
1, 5, 17, 110, 394, 4884, 18108, 294384, 2054736, 27986400, 160460640, 5733590400, 26029779840, 727452230400, 11030096851200, 223495556659200, 1579093018675200, 83918534992588800, 553210247226470400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..19.

FORMULA

E.g.f.: Sum_{k>0} log(1-x^k)/(x^k-1). - Vladeta Jovovic, Aug 01 2004

EXAMPLE

a(6) = 6! *(1 +(1 +1/2) +(1 +1/2 +1/3) +(1 +1/2 +1/3 +1/4 +1/5 +1/6)) because 1, 2, 3 and 6 are the divisors of 6.

CROSSREFS

Sequence in context: A234797 A062586 A301641 * A197912 A203114 A198027

Adjacent sequences:  A067707 A067708 A067709 * A067711 A067712 A067713

KEYWORD

nonn

AUTHOR

Leroy Quet, Feb 05 2002

STATUS

approved

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Last modified October 16 11:25 EDT 2018. Contains 316263 sequences. (Running on oeis4.)