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 A121414 Column 2 of triangle A121412, in which row n of T=A121412 equals row (n-1) of T^(n+1) with an appended '1'. 7
 1, 1, 5, 45, 581, 9730, 199692, 4843125, 135345925, 4278317373, 150818840250, 5863215069621, 249105031449435, 11480173020040450, 570303168053225908, 30375972794764190385, 1726700205634807475115, 104332294453480284687895 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Also equals column 4 of triangle A101479. LINKS PROG (PARI) {a(n)=local(A=Mat(1), B); for(m=1, n+3, 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^1)[n+3, 3])} CROSSREFS Cf. A121412 (triangle); other columns: A101483, A121413, A121415; A101479 (triangle). Sequence in context: A169714 A084095 A174495 * A243678 A097328 A051539 Adjacent sequences: A121411 A121412 A121413 * A121415 A121416 A121417 KEYWORD nonn AUTHOR Paul D. Hanna, Aug 22 2006 STATUS approved

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Last modified January 28 18:00 EST 2023. Contains 359895 sequences. (Running on oeis4.)