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Search: id:A027848
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| A027848 |
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Sum_{ d|n } sigma(n/d)*d^4. |
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+0
1
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| 1, 19, 85, 311, 631, 1615, 2409, 4991, 6898, 11989, 14653, 26435, 28575, 45771, 53635, 79887, 83539, 131062, 130341, 196241, 204765, 278407, 279865, 424235, 394406, 542925, 558778, 749199, 707311
(list; graph; listen)
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OFFSET
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1,2
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FORMULA
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Dirichlet g.f.: zeta(x-1)zeta(x-4)
Multiplicative with a(p^e) = (p^(4e+7) - (p^3+p^2+p+1)*p^(e+1) + p^2+p+1)/(p^7 - (p^3+p^2+p+1)*p + p^2+p+1). Mitch Harris (Harris.Mitchell(AT)mgh.harvard.edu) Jun 27, 2005.
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PROGRAM
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(PARI from Joerg Arndt (arndt(AT)jjj.de), May 03, 2008)
N=17; default(seriesprecision, N); x=z+O(z^(N+1))
c=sum(j=1, N, j*x^j);
t=1/prod(j=1, N, eta(x^(j))^(j^3))
t=log(t)
t=serconvol(t, c)
Vec(t)
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CROSSREFS
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Sequence in context: A062639 A039609 A063496 this_sequence A039454 A142089 A124947
Adjacent sequences: A027845 A027846 A027847 this_sequence A027849 A027850 A027851
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KEYWORD
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nonn,mult
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AUTHOR
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N. J. A. Sloane (njas(AT)research.att.com).
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