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Search: id:A158876
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| A158876 |
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E.g.f.: exp( Sum_{n>=1} (n-1)!*x^n ). |
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+0
2
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| 1, 1, 3, 19, 217, 4041, 113611, 4532683, 244208049, 17085010897, 1504881245971, 162835665686211, 21219897528855433, 3276502399914104089, 591351260856215820507, 123322423833602768272891
(list; graph; listen)
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OFFSET
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0,3
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FORMULA
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a(n) = (n-1)!*Sum_{k=1..n} k!*a(n-k)/(n-k)! for n>0 with a(0)=1.
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EXAMPLE
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E.g.f.: A(x) = 1 + x + 3*x^2/2! + 19*x^3/3! + 217*x^4/4! +...
log(A(x)) = x + x^2 + 2!*x^3 + 3!*x^4 +...+ (n-1)!*x^n +....
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PROGRAM
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(PARI) {a(n)=if(n==0, 1, (n-1)!*sum(k=1, n, k!*a(n-k)/(n-k)!))}
(PARI) {a(n)=n!*polcoeff(exp(sum(k=1, n, (k-1)!*x^k)+x*O(x^n)), n)}
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CROSSREFS
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Cf. A000142, A122949.
Sequence in context: A074707 A135749 A005647 this_sequence A001833 A001035 A166380
Adjacent sequences: A158873 A158874 A158875 this_sequence A158877 A158878 A158879
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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), Apr 13 2009
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