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%I #8 Jun 10 2023 08:09:30
%S 1,3,-1,4,-1,-1,7,-4,0,0,6,-1,-1,-1,-1,12,-8,-3,1,1,1,8,-1,-1,-1,-1,
%T -1,-1,15,-11,0,0,0,0,0,0,13,-5,-5,0,0,0,0,0,0,18,-10,-3,-3,-3,1,1,1,
%U 1,1,12,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,28,-27,-7,4,4,4,0,0,0,0,0,0
%N Triangle read by rows, A051731 * A143318; 1<=k<=n.
%C Left border = sigma(n), A000203.
%C Right border = mu(n) A008683.
%C Row sums = d(n), A000005.
%e First few rows of the triangle =
%e 1;
%e 3, -1;
%e 4, -1, -1;
%e 7, -4, 0, 0;
%e 6, -1, -1, -1, -1;
%e 12, -8, -3, -1, -1, -1;
%e 8, -1, -1, -1, -1, -1, -1;
%e ...
%Y Cf. A000005, A000203, A008683, A051731, A143318.
%K tabl,sign
%O 1,2
%A _Gary W. Adamson_, Aug 07 2008
%E a(69) = -7 corrected by _Georg Fischer_, Jun 10 2023