|
| |
|
|
A113997
|
|
Row sums of triangle A113993, where column k equals column 0 of A113983^(k+1).
|
|
4
|
|
|
|
1, 2, 4, 9, 23, 68, 232, 909, 4061, 20538, 116736, 740473, 5206295, 40317216, 341837416, 3156076177, 31572353377, 340658773754, 3948027171748, 48959894881537, 647431703490895, 9100410418912740, 135573816069186800
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,2
|
|
|
LINKS
|
Table of n, a(n) for n=0..22.
|
|
|
EXAMPLE
|
Triangle A113993 begins:
1;
1,1;
1,2,1;
1,4,3,1;
1,8,9,4,1;
1,18,27,16,5,1;
1,46,89,64,25,6,1;
1,136,327,276,125,36,7,1;
1,464,1353,1304,665,216,49,8,1; ...
|
|
|
PROG
|
(PARI) a(n)=local(A, B); A=Mat(1); for(m=2, n+2, B=matrix(m, m); for(i=1, m, for(j=1, i, if(i<3 || j==1 || j==i, B[i, j]=1, B[i, j]=A[i-1, j-1]+(A^2)[i-2, j-1] ); )); A=B); sum(k=0, n, (A^(k+1))[n-k+1, 1])
|
|
|
CROSSREFS
|
Cf. A113993, A113989 (column 1), A113994 (column 2), A113995 (column 3), A113996 (column 4), A113983.
Sequence in context: A088930 A225588 A089844 * A125789 A058731 A291981
Adjacent sequences: A113994 A113995 A113996 * A113998 A113999 A114000
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
Paul D. Hanna, Nov 12 2005
|
|
|
STATUS
|
approved
|
| |
|
|
