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 A127192 Triangle, square of A054523; row sums = A018804. 2
 1, 2, 1, 4, 0, 1, 5, 2, 0, 1, 8, 0, 0, 0, 1, 8, 4, 2, 0, 0, 1, 12, 0, 0, 0, 0, 0, 1, 8, 4, 2, 0, 0, 1, 12, 0, 0, 0, 0, 0, 1, 12, 5, 0, 2, 0, 0, 0, 1, 16, 0, 4, 0, 0, 0, 0, 0, 1, 16, 8, 0, 0, 2, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums = A018804: (1, 3, 5, 8, 9, 15,...), Sum of gcd(k,n) for 1<= k <= n. Left column = A029935: (1, 2, 4, 5, 8, 8, 12, 12,...). A127192 * d(n) = d(n) * n, or A127192 * A000005 = A038040 = (1, 4, 6, 12, 10, 24, 14,...). LINKS FORMULA Triangle, Square of A054523 By columns, parsed terms of A029935 interspersed with (k-1) zeros. EXAMPLE First few rows of the triangle are: 1; 2, 1; 4, 0, 1; 5, 2, 0, 1; 8, 0, 0, 0, 1; 8, 4, 2, 0, 0, 1; 12, 0, 0, 0, 0, 0, 1; 12, 5, 0, 2, 0, 0, 0, 1; 16, 0, 4, 0, 0, 0, 0, 0, 1; ... CROSSREFS Cf. A029935, A018804, A054523, A000005, A038040. Sequence in context: A016585 A309054 A143316 * A122141 A091604 A200192 Adjacent sequences:  A127189 A127190 A127191 * A127193 A127194 A127195 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Jan 07 2007 STATUS approved

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Last modified April 9 07:41 EDT 2020. Contains 333344 sequences. (Running on oeis4.)