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A113147
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Row 6 of table A113143; equal to INVERT of 6-fold factorials shifted one place right.
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1
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1, 1, 2, 10, 110, 1954, 47270, 1437562, 52531310, 2239259266, 109021857446, 5966767051354, 362558298692270, 24214789406313442, 1763062297639690790, 138975554045857840570, 11790733617760291994990, 1071215297856049456744642
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OFFSET
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0,3
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LINKS
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Table of n, a(n) for n=0..17.
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FORMULA
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a(n) = Sum_{j=0..k} 6^(k-j)*A111146(k, j).
a(0) = 1; a(n+1) = Sum_{k=0..n} a(k)*A008542(n-k).
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EXAMPLE
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A(x) = 1 + x + 2*x^2 + 10*x^3 + 110*x^4 + 1954*x^5 +...
= 1/(1 - x - x^2 - 7*x^3 - 91*x^4 -...- A008542(n)*x^(n+1)
-...).
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PROG
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(PARI) {a(n)=local(x=X+X*O(X^n)); A=1/(1-x-x^2*sum(j=0, n, x^j*prod(i=0, j, 6*i+1))); return(polcoeff(A, n, X))}
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CROSSREFS
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Cf. A113143, A008542 (6-fold factorials).
Sequence in context: A212491 A006608 A066205 * A335946 A206154 A181445
Adjacent sequences: A113144 A113145 A113146 * A113148 A113149 A113150
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KEYWORD
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nonn
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AUTHOR
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Philippe Deléham and Paul D. Hanna, Oct 28 2005
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STATUS
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approved
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