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%I #7 Feb 15 2022 11:12:07
%S 1,1,4,2,4,9,3,6,9,16,4,8,12,16,25,5,10,15,20,25,36,6,12,18,24,30,36,
%T 49,7,14,21,28,35,42,49,64,8,16,24,32,40,48,56,64,81,9,18,27,36,45,54,
%U 63,72,81,100
%N A128132 * A002260.
%C Row sums = A006003: (1, 5, 15, 34, 65, ...).
%C A002260 * A128132 = A128137.
%F A128132 * A002260 as infinite lower triangular matrices.
%e First few rows of the triangle:
%e 1;
%e 1, 4;
%e 2, 4, 9;
%e 3, 6, 9, 16;
%e 4, 8, 12, 16, 25;
%e 5, 10, 15, 20, 25, 36;
%e 6, 12, 18, 24, 30, 36, 49;
%e ...
%Y Cf. A128132, A002260, A006003, A128137.
%K nonn,tabl
%O 1,3
%A _Gary W. Adamson_, Feb 16 2007