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A104991 Row sums of triangle A104990, which equals the matrix cube of triangle A104980. 1
1, 4, 22, 142, 1048, 8704, 80386, 817786, 9093340, 109794556, 1431360958, 20047830262, 300343272952, 4793871035416, 81232799446906, 1456671526257106, 27562347560513524, 548844246683051860, 11474015910364016086 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..18.

PROG

(PARI) {a(n)=if(n<0, 0, sum(k=0, n, (matrix(n+1, n+1, 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))))^-3)[n+1, k+1]))}

CROSSREFS

Cf. A104990, A104980.

Sequence in context: A190271 A045744 A243626 * A027391 A134988 A081002

Adjacent sequences:  A104988 A104989 A104990 * A104992 A104993 A104994

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Apr 10 2005

STATUS

approved

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Last modified August 10 16:56 EDT 2020. Contains 336381 sequences. (Running on oeis4.)