A135858 - OEIS

%I #5 Mar 27 2022 22:25:40

%S 1,3,1,7,5,1,13,13,7,1,21,21,21,9,1,31,31,31,31,11,1,43,43,43,43,43,

%T 13,1,57,57,57,57,57,57,15,1,73,73,73,73,73,73,73,17,1,91,91,91,91,91,

%U 91,91,91,19,1

%N A128229^2 * A000012.

%C Row sums = A135859: (1, 4, 13, 34, 73, 136, ...).

%F A128229^2 * A000012, where A128229 = a bidiagonal matrix with all 1's in the main diagonal and (1, 2, 3, ...) in the subdiagonal.

%e First few rows of the triangle:

%e    1;

%e    3,  1;

%e    7,  5,  1;

%e   13, 13,  7,  1;

%e   21, 21, 21,  9,  1;

%e   31, 31, 31, 31, 11,  1;

%e   43, 43, 43, 43, 43, 13, 1;

%e   ...

%Y Cf. A128229, A135859.

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, Dec 01 2007