%I #11 May 29 2023 13:19:48
%S 1,2,0,2,1,0,3,0,1,0,2,1,1,1,0,4,1,0,0,1,0,2,1,1,1,1,1,0,4,0,2,0,1,0,
%T 1,0,3,2,0,1,1,0,1,1,0,4,1,2,1,0,0,1,0,1,0,2,1,1,1,1,1,1,1,1,1,0,6,1,
%U 1,0,2,0,1,0,0,0,1,0
%N Triangle read by rows: A051731 * A054521, as infinite lower triangular matrices.
%C Row sums = n, left column = d(n), (A000005: 1, 2, 2, 3, 2, 4, 2, ...).
%F Inverse Moebius transform of A054521.
%e First few rows of the triangle:
%e 1;
%e 2, 0;
%e 2, 1, 0;
%e 3, 0, 1, 0;
%e 2, 1, 1, 1, 0;
%e 4, 1, 0, 0, 1, 0;
%e 2, 1, 1, 1, 1, 1, 0;
%e 4, 0, 2, 0, 1, 0, 1, 0;
%e 3, 2, 0, 1, 1, 0, 1, 1, 0;
%e ...
%Y Cf. A000005, A051731, A054521.
%K nonn,tabl
%O 1,2
%A _Gary W. Adamson_, Jan 12 2007
%E Definition clarified, a(56) corrected and more terms from _Georg Fischer_, May 29 2023
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