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 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 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

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Last modified March 22 18:15 EDT 2023. Contains 361432 sequences. (Running on oeis4.)