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 A127649 A127648 * A054523 as infinite lower triangular matrices. 1
 1, 2, 2, 6, 0, 3, 8, 4, 0, 4, 20, 0, 0, 0, 5, 12, 12, 6, 0, 0, 6, 42, 0, 0, 0, 0, 0, 7, 32, 16, 0, 8, 0, 0, 0, 8, 54, 0, 18, 0, 0, 0, 0, 0, 9, 40, 40, 0, 0, 10, 0, 0, 0, 0, 10, 110, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, 48, 24, 24, 24, 0, 12, 0, 0, 0, 0, 0, 12, 156, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 13, 84 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Natural number transform of A054523. Row sums = n^2, left column = A002618 LINKS FORMULA T(n,k)=n*A054523(n,k). - R. J. Mathar, Nov 01 2007 EXAMPLE First few rows of the triangle are: 1; 2, 2; 6, 0, 3; 8, 4, 0, 4; 20, 0, 0, 0, 5; 12, 12, 6, 0, 0, 6; 42, 0, 0, 0, 0, 0, 7; ... MAPLE A054523 := proc(n, k) if n mod k = 0 then numtheory[phi](n/k) ; else 0 ; fi ; end: A127649 := proc(n, k) A054523(n, k)*n ; end: for n from 1 to 20 do for k from 1 to n do printf("%d, ", A127649(n, k)) ; od: od: # R. J. Mathar, Nov 01 2007 CROSSREFS Cf. A127648, A002618, A054523. Sequence in context: A163119 A091085 A011144 * A274440 A199220 A047916 Adjacent sequences: A127646 A127647 A127648 * A127650 A127651 A127652 KEYWORD nonn,tabl,easy AUTHOR Gary W. Adamson, Jan 22 2007 EXTENSIONS More terms from R. J. Mathar, Nov 01 2007 STATUS approved

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Last modified December 6 15:54 EST 2022. Contains 358644 sequences. (Running on oeis4.)