A065234 Fill a triangular array by rows by writing numbers 1 up to b(0), 1 up to b(1), etc., where b(n) are the decagonal numbers. The first elements of the rows form a(n).
1, 1, 3, 6, 10, 5, 11, 18, 26, 8, 18, 29, 41, 2, 16, 31, 47, 64, 82, 16, 36, 57, 79, 102, 126, 25, 51, 78, 106, 135, 165, 21, 53, 86, 120, 155, 191, 228, 34, 73, 113, 154, 196, 239, 283, 31, 77, 124, 172, 221, 271, 322, 4, 57, 111, 166, 222, 279, 337, 396, 5, 66, 128
Offset: 0