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A127475 Triangle T(n,k) read by rows: T(n,k) = mu(n)*phi(k) if k|n, else T(n,k)=0.

%I A127475 #5 Mar 30 2012 17:25:15
%S A127475 1,-1,-1,-1,0,-2,0,0,0,0,-1,0,0,0,-4,1,1,2,0,0,2,-1,0,0,0,0,0,-6,0,0,
%T A127475 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,4,0,0,0,0,4,-1,0,0,0,0,0,0,0,0,
%U A127475 0,-10,0,0,0,0,0,0,0,0,0,0,0,0,-1,0,0,0,0,0,0,0,0,0,0,0,-12
%N A127475 Triangle T(n,k) read by rows: T(n,k) = mu(n)*phi(k) if k|n, else T(n,k)=0.
%F A127475 T(n,k) = A054522(n,k)*A008683(n).
%F A127475 T(n,1) = A008683(n) = mu(n).
%F A127475 T(n,n) = A097945(n).
%e A127475 The triangle starts in row n=1 as:
%e A127475 1;
%e A127475 -1, -1;
%e A127475 -1, 0, -2;
%e A127475 0, 0, 0, 0;
%e A127475 -1, 0, 0, 0, -4;
%e A127475 1, 1, 2, 0, 0, 2;
%e A127475 -1, 0, 0, 0, 0, 0, -6;
%e A127475 ...
%Y A127475 Cf. A008683, A054522, A055615 (row sums), A097945, A023900.
%K A127475 tabl,easy,sign
%O A127475 1,6
%A A127475 _Gary W. Adamson_, Jan 15 2007