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 A121417 Column 1 of triangle A121416. 8
 1, 2, 9, 69, 769, 11346, 208914, 4613976, 118840164, 3496297632, 115638728395, 4246267163601, 171369282105510, 7538270885559264, 358926669220446804, 18389706733665138450, 1008742283718489346668, 58981158542987625464424 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Also column 1 of square array A136737. A121416 is the matrix square of triangle A121412; row n of triangle T=A121412 equals row (n-1) of T^(n+1) with an appended '1'. LINKS PROG (PARI) {a(n)=local(A=Mat(1), B); for(m=1, n+2, 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^2)[n+2, 2])} CROSSREFS Cf. A121416 (triangle); other columns: A121418, A121419. Cf. A136737; A121413, A121422; A121427, A136741. Sequence in context: A319285 A316652 A330471 * A232549 A284762 A296718 Adjacent sequences: A121414 A121415 A121416 * A121418 A121419 A121420 KEYWORD nonn AUTHOR Paul D. Hanna, Aug 22 2006 EXTENSIONS Edited by N. J. A. Sloane, Oct 30 2008 at the suggestion of R. J. Mathar STATUS approved

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Last modified March 25 06:19 EDT 2023. Contains 361511 sequences. (Running on oeis4.)