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 A143425 Triangle read by rows A051731 * A130123, 1<=k<=n. 1
 1, 1, 2, 1, 0, 4, 1, 2, 0, 8, 1, 0, 0, 0, 16, 1, 2, 4, 0, 0, 32, 1, 0, 0, 0, 0, 0, 64, 1, 2, 0, 8, 0, 0, 0, 128, 1, 0, 4, 0, 0, 0, 0, 0, 256, 1, 2, 0, 0, 16, 0, 0, 0, 0, 512, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1024, 1, 2, 4, 8, 0, 32, 0, 0, 0, 0, 0, 2048 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Row sums = A034729: (1, 3, 5, 11, 17, ...). LINKS Table of n, a(n) for n=1..78. FORMULA Triangle read by rows A051731 * A130123, 1<=k<=n, where A130123 = an infinite lower triangular matrix with (1, 2, 4, 8, ...) in the main diagonal and the rest zeros. A051731 = the inverse Mobius transform. EXAMPLE First few rows of the triangle are: 1; 1, 2; 1, 0, 4; 1, 2, 0, 8; 1, 0, 0, 0, 16; 1, 2, 4, 0, 0, 32; ... PROG (PARI) tabl(nn) = {ma = matrix(nn, nn, n, k, !(n%k)); mb = matrix(nn, nn, n, k, n--; k--; if (n==k, 2^n, 0)); m = ma*mb; for (n=1, nn, for (k=1, n, print1(m[n, k], ", "); ); print(); ); } \\ Michel Marcus, Jun 30 2017 CROSSREFS Cf. A034729, A051731, A130123. Sequence in context: A140882 A334044 A143724 * A323376 A166555 A136329 Adjacent sequences: A143422 A143423 A143424 * A143426 A143427 A143428 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Aug 14 2008 EXTENSIONS Typo in data corrected by Michel Marcus, Jun 30 2017 STATUS approved

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Last modified December 8 14:30 EST 2023. Contains 367679 sequences. (Running on oeis4.)