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 A185621 Column 1 of triangular matrix T = A185620, which satisfies: T^3 - T^2 + I = SHIFT_LEFT(T). 3
 1, 1, 3, 10, 42, 226, 1525, 12555, 123098, 1408656, 18499835, 274937571, 4569703790, 84104161618, 1699644180677, 37442806230267, 893577983768401, 22976420374082264, 633487846228307145, 18649221873212499505 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS PROG (PARI) {A185620(n, k)=local(A=Mat(1), B); for(m=1, n, B=A^3-A^2+A^0; A=matrix(m+1, m+1); for(i=1, m+1, for(j=1, i, if(i<2|j==i, A[i, j]=1, if(j==1, A[i, j]=1, A[i, j]=B[i-1, j-1]))))); return(A[n+1, k+1])} /* Column 1: */ {a(n)=A185620(n+1, 1)} CROSSREFS Cf. A185620, A185622, A185623. Sequence in context: A007680 A232606 A334270 * A190657 A143523 A288813 Adjacent sequences: A185618 A185619 A185620 * A185622 A185623 A185624 KEYWORD nonn AUTHOR Paul D. Hanna, Feb 01 2011 STATUS approved

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Last modified February 5 02:12 EST 2023. Contains 360082 sequences. (Running on oeis4.)