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 A127572 Triangle, T(n,k) = sigma(k) * n/k if k|n, T(n,k) = 0 otherwise. 0
 1, 2, 3, 3, 0, 4, 4, 6, 0, 7, 5, 0, 0, 0, 6, 6, 9, 8, 0, 0, 12, 7, 0, 0, 0, 0, 0, 8, 8, 12, 0, 14, 0, 0, 0, 15, 9, 0, 12, 0, 0, 0, 0, 0, 13, 10, 15, 0, 0, 12, 0, 0, 0, 0, 18 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA A126988 * M, where M = an infinite matrix with sigma(n) in the main diagonal and the rest zeros. EXAMPLE First few rows of the triangle are: 1; 2, 3; 3, 0, 4; 4, 6, 0, 7; 5, 0, 0, 0, 6; 6, 9, 8, 0, 0, 12; ... CROSSREFS Main diagonal = sigma(n), A000203; row sums = A060640. Cf. A126988. Sequence in context: A026932 A087401 A192498 * A021815 A238525 A075255 Adjacent sequences:  A127569 A127570 A127571 * A127573 A127574 A127575 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Jan 19 2007 EXTENSIONS Edited by Franklin T. Adams-Watters, Aug 24 2011 STATUS approved

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