%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