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 A127651 Triangle T(n,k) = n*k if k|n, 0 otherwise; 1<=k<=n. 1
 1, 2, 4, 3, 0, 9, 4, 8, 0, 16, 5, 0, 0, 0, 25, 6, 12, 18, 0, 0, 36, 7, 0, 0, 0, 0, 0, 49, 8, 16, 0, 32, 0, 0, 0, 64, 9, 0, 27, 0, 0, 0, 0, 0, 81, 10, 20, 0, 0, 50, 0, 0, 0, 0, 100, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 121, 12, 24, 36, 48, 0, 72, 0, 0, 0, 0, 0, 144 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Equals the matrix product A127648 * A127093 as infinite lower triangular matrices. LINKS FORMULA T(n,k) = n*A127093(n,k). - R. J. Mathar, Oct 01 2011 EXAMPLE First few rows of the triangle are: 1; 2, 4; 3, 0, 9; 4, 8, 0, 16; 5, 0, 0, 0, 25; 6, 12, 18, 0, 0, 36; 7, 0, 0, 0, 0, 0, 49; 8, 16, 0, 32, 0, 0, 0, 64; ... MAPLE A127651 := proc(n, k) if n mod k =0 then n*k; else 0 ; end if; end proc: # R. J. Mathar, Oct 01 2011 CROSSREFS Cf. A127648, A127093, A064987 (row sums). Sequence in context: A246713 A106137 A213381 * A019641 A085008 A285587 Adjacent sequences: A127648 A127649 A127650 * A127652 A127653 A127654 KEYWORD nonn,tabl,easy AUTHOR Gary W. Adamson, Jan 22 2007 STATUS approved

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Last modified December 6 16:00 EST 2022. Contains 358644 sequences. (Running on oeis4.)