%I #3 Mar 30 2012 17:25:33
%S 1,2,1,2,0,2,3,0,2,2,2,-2,1,1,4,4,-2,3,0,5,2,2,-4,0,-1,4,1,6,4,-5,2,
%T -1,4,1,6,4,3,-6,1,-3,4,-2,6,4,6,4,-8,0,-4,8,-3,7,3,7,4,2,-8,-2,-6,3,
%U -4,6,2,6,3,10
%N Triangle read by rows, A051731 * A000012 * A051731 * A054533
%C Row sums = sigma(n), A000203.
%C Right border = phi(n), A000010
%C Left border = d(n), A000005
%F Triangle read by rows, A051731 * A000012 * A051731 * A054533; as infinite lower triangular matrices.
%e First few rows of the triangle =
%e 1;
%e 2, 1;
%e 2, 0, 2;
%e 3, 0, 2, 2;
%e 2, -2, 1, 1, 4;
%e 4, -2, 3, 0, 5, 2;
%e 2, -4, 0, -1, 4, 1, 6;
%e 4, -5, 2, -1, 4, 1, 6, 4;
%e 3, -6, 1, -3, 4, -2, 6, 4, 6;
%e 4, -8, 0, -4, 8, -3, 7, 3, 7, 4;
%e ...
%Y A054533, Cf. A000203, A000005, A000010, A051731
%K tabl,sign
%O 1,2
%A _Gary W. Adamson_, Sep 20 2008