A127737 - OEIS

%I #5 Feb 14 2022 23:36:42

%S 1,3,4,3,7,9,3,7,13,16,3,7,13,21,25,3,7,13,21,31,36,3,7,13,21,31,43,

%T 49,3,7,13,21,31,43,57,64,3,7,13,21,31,43,57,73,81,3,7,13,21,31,43,57,

%U 73,91,100

%N A002260 * A127701.

%C Deleting the right border (1, 4, 9, 16, ...), rows tend to A002061 starting (3, 7, 13, 21, 31, ...). Row sums = A108766: (1, 7, 19, 39, 69, 111, ...).

%F A002260 * A127701 as infinite lower triangular matrices.

%e First few rows of the triangle:

%e   1;

%e   3, 4;

%e   3, 7,  9;

%e   3, 7, 13, 16;

%e   3, 7, 13, 21, 25;

%e   ...

%Y Cf. A002260, A127701, A108766, A002061.

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, Jan 27 2007