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Search: id:A158108
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| A158108 |
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L.g.f.: exp(Sum_{n>=1} a(n)*x^n/n) = 1 + x*exp(Sum_{n>=1} sigma(n)*a(n)*x^n/n). |
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+0
3
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| 1, 1, 4, 21, 186, 1366, 19433, 180541, 3083809, 44941136, 895695901, 11809732422, 359749783368, 5445775854961, 140573612743254, 3607678852423757, 119036988031104164, 2273841364845589333, 93765800142590570954
(list; graph; listen)
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OFFSET
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1,3
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FORMULA
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L.g.f.: exp(Sum_{n>=1} a(n)*x^n/n) = 1 + x*G(x) where G(x) = g.f. of A158107.
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PROGRAM
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(PARI) {a(n)=local(A=x+x^2); if(n==0, 1, for(i=1, n-1, A=log(1+x*exp(sum(m=1, n, sigma(m)*x^m*polcoeff(A+x*O(x^m), m) )+x*O(x^n)))); n*polcoeff(A, n))}
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CROSSREFS
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Cf. A158107.
Sequence in context: A008858 A078670 A163948 this_sequence A158258 A065527 A041667
Adjacent sequences: A158105 A158106 A158107 this_sequence A158109 A158110 A158111
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KEYWORD
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nonn
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AUTHOR
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Paul D. Hanna (pauldhanna(AT)juno.com), Mar 28 2009
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