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A113345
Matrix square of triangle A113340.
9
1, 2, 1, 5, 6, 1, 19, 39, 10, 1, 113, 327, 105, 14, 1, 966, 3556, 1315, 203, 18, 1, 10958, 48659, 19875, 3367, 333, 22, 1, 156700, 812462, 357860, 64750, 6867, 495, 26, 1, 2727794, 16136404, 7547602, 1435497, 160005, 12199, 689, 30, 1
OFFSET
0,2
COMMENTS
Transforms column k of triangle A113340 into column k+1 of A113340. Also transforms column k of triangle A113350 into column k+1 of A113350.
EXAMPLE
Matrix square A113340^2 starts:
1;
2,1;
5,6,1;
19,39,10,1;
113,327,105,14,1;
966,3556,1315,203,18,1;
10958,48659,19875,3367,333,22,1;
156700,812462,357860,64750,6867,495,26,1;
2727794,16136404,7547602,1435497,160005,12199,689,30,1; ...
PROG
(PARI) T(n, k)=local(A, B); A=matrix(1, 1); A[1, 1]=1; for(m=2, n+1, B=matrix(m, m); for(i=1, m, for(j=1, i, if(i<3 || j==i || j>m-1, B[i, j]=1, if(j==1, B[i, 1]=1, B[i, j]=(A^(2*j-1))[i-j+1, 1])); )); A=B); (A^2)[n+1, k+1]
CROSSREFS
Cf. A113340, A113346 (column 0), A113347 (column 1), A113348 (column 2), A113349 (column 3); A113350.
Sequence in context: A124575 A178121 A302595 * A078123 A342968 A323312
KEYWORD
nonn,tabl
AUTHOR
Paul D. Hanna, Nov 08 2005
STATUS
approved