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A027847
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Sum sigma(n/d)*d^3; d|n.
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0
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1, 11, 31, 95, 131, 341, 351, 775, 850, 1441, 1343, 2945, 2211, 3861, 4061, 6231, 4931, 9350, 6879, 12445, 10881, 14773, 12191, 24025, 16406, 24321, 22990, 33345, 24419, 44671, 29823, 49911, 41633, 54241, 45981, 80750, 50691, 75669, 68541, 101525, 68963, 119691, 79551, 127585, 111350
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| Dirichlet g.f.: zeta(x-1)*zeta(x-3)
Multiplicative with a(p^e) = (p^(3e+5) - (p^2+p+1)*p^(e+1) + p+1)/(p^5 - (p^2+p+1)*p + p + 1). [Mitch Harris, Jun 27 2005]
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PROG
| (PARI) N=66; x='x+O('x^N); /* that many terms */
c=sum(j=1, N, j*x^j);
t=log(1/prod(j=1, N, eta(x^(j))^(j^2)));
Vec(serconvol(t, c)) /* show terms */
/* Joerg Arndt, May 03 2008 */
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CROSSREFS
| Sequence in context: A126365 A082102 A199112 * A068841 A192246 A124296
Adjacent sequences: A027844 A027845 A027846 * A027848 A027849 A027850
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KEYWORD
| nonn,mult
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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