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A104990 Matrix cube of triangle A104980. 2
1, 3, 1, 15, 6, 1, 93, 39, 9, 1, 675, 285, 75, 12, 1, 5577, 2331, 657, 123, 15, 1, 51555, 21153, 6207, 1269, 183, 18, 1, 526809, 211227, 63549, 13743, 2181, 255, 21, 1, 5895819, 2304321, 704319, 158325, 26739, 3453, 339, 24, 1, 71733585, 27291843 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Triangular matrix A104980 satisfies: SHIFT_LEFT(column 0 of A104980^p) = p*(column p+1 of A104980) for p>=0.

LINKS

Table of n, a(n) for n=0..46.

FORMULA

T(n+1, 0) = 3*A104980(n+4, 4) for n>=0.

EXAMPLE

Triangle begins:

1;

3,1;

15,6,1;

93,39,9,1;

675,285,75,12,1;

5577,2331,657,123,15,1;

51555,21153,6207,1269,183,18,1;

526809,211227,63549,13743,2181,255,21,1;

5895819,2304321,704319,158325,26739,3453,339,24,1;

71733585,27291843,8424813,1947711,343641,47355,5145,435,27,1; ...

PROG

(PARI) T(n, k)=if(n<k || k<0, 0, (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. A104980, A104982 (column 0), A104991 (row sums).

Sequence in context: A092589 A048966 A297704 * A089463 A136231 A113389

Adjacent sequences:  A104987 A104988 A104989 * A104991 A104992 A104993

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna, Apr 10 2005

STATUS

approved

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Last modified September 23 22:32 EDT 2020. Contains 337315 sequences. (Running on oeis4.)