A023566 Convolution of A023531 and A014306.
0, 0, 1, 1, 0, 2, 2, 1, 2, 3, 2, 2, 3, 2, 4, 4, 3, 3, 4, 4, 4, 5, 3, 4, 5, 5, 5, 5, 5, 5, 6, 6, 5, 6, 6, 5, 7, 6, 5, 7, 7, 7, 6, 6, 8, 7, 7, 7, 8, 8, 8, 8, 7, 6, 9, 9, 7, 9, 9, 8, 8, 9, 7, 8, 9, 10, 10, 9, 8, 10, 10, 10, 9, 9, 9, 10, 10, 10, 11, 10, 11, 10, 11, 10, 10, 10, 11, 9, 11, 10
Offset: 1