A131768 2*(A007318 * A097807) - A000012.
1, 3, 1, 5, 5, 1, 7, 11, 7, 1, 9, 19, 19, 9, 1, 11, 29, 39, 29, 11, 1, 13, 41, 69, 69, 41, 13, 1, 15, 55, 111, 139, 111, 55, 15, 1, 17, 71, 167, 251, 251, 167, 71, 17, 1, 19, 89, 239, 419, 503, 419, 239, 89, 19, 1
Offset: 0
Examples
First few rows of the triangle: 1; 3, 1; 5, 5, 1; 7, 11, 7, 1; 9, 19, 19, 9, 1; 11, 29, 39, 29, 11, 1; 13, 41, 69, 69, 41, 13, 1; 15, 55, 111, 139, 111, 55, 15, 1; ...
Comments