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A104981
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Column 1 of triangle A104980; also equals column 0 of triangle A104986, which equals the matrix logartithm of A104980.
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5
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0, 1, 2, 7, 33, 191, 1297, 10063, 87669, 847015, 8989301, 103996703, 1303132269, 17589153719, 254509227541, 3931158238735, 64573130459613, 1124144767682215, 20677664894412965, 400760695386194687, 8163539437728923181
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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FORMULA
| Let M = triangle A128175 as an infinite square production matrix: (deleting the first "1"):
1, 1, 0, 0, 0,...
2, 2, 1, 0, 0,...
4, 4, 3, 1, 0,...
8, 8, 7, 4, 1,...
...
a(n) = sum of top row terms of M^(n-1). Example: top row of M^4 = (71, 71, 38, 10, 1), sum = 191 = a(5). - Gary W. Adamson, Jul 14 2011
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PROG
| (PARI) {a(n)=if(n<0, 0, (matrix(n+2, n+2, m, j, if(m==j, 1, if(m==j+1, -m+1, -polcoeff((1-1/sum(i=0, m, i!*x^i))/x+O(x^m), m-j-1))))^-1)[n+1, 2])}
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CROSSREFS
| Cf. A104980, A104986.
Cf. A128175
Sequence in context: A172387 A186760 A162661 * A121965 A058797 A006595
Adjacent sequences: A104978 A104979 A104980 * A104982 A104983 A104984
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KEYWORD
| nonn
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AUTHOR
| Paul D. Hanna (pauldhanna(AT)juno.com), Apr 10 2005
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