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A121420 Matrix cube of triangle A121412. 12
1, 3, 1, 12, 3, 1, 76, 15, 3, 1, 711, 118, 18, 3, 1, 9054, 1317, 169, 21, 3, 1, 147471, 19311, 2190, 229, 24, 3, 1, 2938176, 352636, 36360, 3378, 298, 27, 3, 1, 69328365, 7722840, 737051, 62655, 4929, 376, 30, 3, 1, 1891371807, 197354133, 17645187 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Row n of triangle T=A121412 equals row (n-1) of T^(n+1) with an appended '1'.

EXAMPLE

Triangle begins:

1;

3, 1;

12, 3, 1;

76, 15, 3, 1;

711, 118, 18, 3, 1;

9054, 1317, 169, 21, 3, 1;

147471, 19311, 2190, 229, 24, 3, 1;

2938176, 352636, 36360, 3378, 298, 27, 3, 1;

69328365, 7722840, 737051, 62655, 4929, 376, 30, 3, 1; ...

PROG

(PARI) {T(n, k)=local(A=Mat(1), B); for(m=1, n+1, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=1, B[i, j]=(A^i)[i-1, j]); )); A=B); return((A^3)[n+1, k+1])}

CROSSREFS

Cf. A121412, A121416; A101479; columns: A121421, A121422, A121423.

Sequence in context: A124572 A144880 A144881 * A117375 A162995 A177020

Adjacent sequences:  A121417 A121418 A121419 * A121421 A121422 A121423

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Aug 23 2006

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Last modified February 17 10:05 EST 2012. Contains 206009 sequences.