A065230 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 hexagonal numbers. The first elements of the rows form a(n).

1, 1, 3, 6, 4, 9, 15, 7, 15, 24, 6, 17, 29, 42, 11, 26, 42, 59, 11, 30, 50, 71, 2, 25, 49, 74, 100, 7, 35, 64, 94, 125, 4, 37, 71, 106, 142, 179, 27, 66, 106, 147, 189, 1, 45, 90, 136, 183, 231, 4, 54, 105, 157, 210, 264, 319, 50, 107, 165, 224, 284, 345, 29, 92, 156, 221