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Triangle read by rows: A107131 * A000012.
2

%I #14 Apr 02 2022 08:20:23

%S 1,1,1,2,2,1,4,4,4,1,9,9,9,7,1,21,21,21,21,11,1,51,51,51,51,46,16,1,

%T 127,127,127,127,127,92,22,1,323,323,323,323,323,309,169,29,1,835,835,

%U 835,835,835,835,709,289,37,1

%N Triangle read by rows: A107131 * A000012.

%C Row sums = A005773 starting (1, 2, 5, 13, 35, 96, 267, ...).

%C Leftmost column = A001006: (1, 1, 2, 4, 9, 21, 51, ...).

%C A136788 = A000012 * A107131.

%F A107131 * A000012 as infinite lower triangular matrices.

%e First few rows of the triangle:

%e 1;

%e 1, 1;

%e 2, 2, 1;

%e 4, 4, 4, 1;

%e 9, 9, 9, 7, 1;

%e 21, 21, 21, 21, 11, 1;

%e 51, 51, 51, 51, 46, 16, 1;

%e 127, 127, 127, 127, 127, 92, 22, 1;

%e ...

%Y Cf. A005773, A001006, A136788.

%K nonn,tabl

%O 1,4

%A _Gary W. Adamson_, Jan 21 2008