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Triangle read by rows: A054525 * A127481 as infinite lower triangular matrices.
5

%I #12 Sep 24 2018 16:53:14

%S 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,

%T 0,0,0,32,9,0,18,0,0,0,0,0,54,10,10,0,0,40,0,0,0,0,40

%N Triangle read by rows: A054525 * A127481 as infinite lower triangular matrices.

%C Mobius transform of A127481.

%F Sum_{k=1..n} T(n,k) = n^2.

%F T(n,n) = A002618(n) = n*phi(n).

%e First few rows of the triangle are:

%e 1;

%e 2, 2;

%e 3, 0, 6;

%e 4, 4, 0, 8;

%e 5, 0, 0, 0, 20;

%e 6, 6, 12, 0, 0, 12;

%e 7, 0, 0, 0, 0, 0, 42;

%e 8, 8, 0, 16, 0, 0, 0, 32;

%e ...

%p A127466 := proc(n,k)

%p add( A054525(n,j)*A127481(j,k),j=k..n) ;

%p end proc: # _R. J. Mathar_, Sep 06 2013

%Y Cf. A054522, A127093, A062952, A002618.

%Y Cf. A127093, A127481, A054525.

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, Jan 15 2007

%E Edited by _N. J. A. Sloane_ at the suggestion of _Andrew S. Plewe_, Aug 23 2007