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 A127466 Triangle read by rows: A054525 * A127481 as infinite lower triangular matrices. 5
 1, 2, 2, 3, 0, 6, 4, 4, 0, 8, 5, 0, 0, 0, 20, 6, 6, 12, 0, 0, 12, 7, 0, 0, 0, 0, 0, 42, 8, 8, 0, 16, 0, 0, 0, 32, 9, 0, 18, 0, 0, 0, 0, 0, 54, 10, 10, 0, 0, 40, 0, 0, 0, 0, 40 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Mobius transform of A127481. LINKS FORMULA Sum_{k=1..n} T(n,k) = n^2. T(n,n) = A002618(n) = n*phi(n). EXAMPLE First few rows of the triangle are: 1; 2, 2; 3, 0, 6; 4, 4, 0, 8; 5, 0, 0, 0, 20; 6, 6, 12, 0, 0, 12; 7, 0, 0, 0, 0, 0, 42; 8, 8, 0, 16, 0, 0, 0, 32; ... MAPLE A127466 := proc(n, k)     add( A054525(n, j)*A127481(j, k), j=k..n) ; end proc: # R. J. Mathar, Sep 06 2013 CROSSREFS Cf. A054522, A127093, A062952, A002618. Cf. A127093, A127481, A054525. Sequence in context: A330925 A191361 A199784 * A342314 A099118 A320999 Adjacent sequences:  A127463 A127464 A127465 * A127467 A127468 A127469 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Jan 15 2007 EXTENSIONS Edited by N. J. A. Sloane at the suggestion of Andrew S. Plewe, Aug 23 2007 STATUS approved

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Last modified July 28 00:54 EDT 2021. Contains 346316 sequences. (Running on oeis4.)