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%I #4 Feb 20 2022 14:46:56

%S 1,3,4,6,7,9,10,11,13,16,15,16,18,21,25,21,22,24,27,31,36,28,29,31,34,

%T 38,43,49,36,37,39,42,46,51,57,64,45,46,48,51,55,60,66,73,81,55,56,58,

%U 61,65,70,76,83,91,100

%N A002260 * A051340.

%C Row sums = A002412: (1, 7, 22, 50, 95, ...).

%F A002260 * A051340 as infinite lower triangular matrices.

%e First few rows of the triangle:

%e 1;

%e 3, 4;

%e 6, 7, 9;

%e 10, 11, 13, 16;

%e 15, 16, 18, 21, 25,

%e 21, 22, 24, 27, 31, 36;

%e 28, 29, 31, 34, 38, 43, 49;

%e ...

%Y Cf. A002260, A051340, A002412.

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, May 18 2007