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%I #6 Mar 27 2022 23:29:26
%S 1,1,1,1,1,2,1,1,3,5,1,1,3,15,14,1,1,3,23,84,42,1,1,3,27,244,466,132,
%T 1,1,3,28,494,2444,2514,429,1,1,3,28,796,8720,22022,13233,1430,1,1,3,
%U 28,1094,24394,128514,181841,68376,4862
%N A000012 * A122890.
%C Row sums = A003422: (1, 2, 4, 10, 34, 154, 874, ...).
%C Main diagonal = A000108, the Catalan numbers: (1, 1, 2, 5, 14, 42, 132, ...).
%F A000012 * A122890 as infinite lower triangular matrices.
%e First few rows of the triangle:
%e 1;
%e 1, 1;
%e 1, 1, 2;
%e 1, 1, 3, 5;
%e 1, 1, 3, 15, 14;
%e 1, 1, 3, 23, 84, 42;
%e 1, 1, 3, 27, 244, 466, 132;
%e 1, 1, 3, 28, 494, 2444, 2514, 429;
%e ...
%Y Cf. A003422, A122890, A000108.
%K nonn,tabl
%O 0,6
%A _Gary W. Adamson_, Nov 25 2007