A sum over partitions (q=20), see first comment.
A221584
A sum over partitions (q=20), see first comment.
Terms
- a(0) =1a(1) =19a(2) =399a(3) =7980a(4) =159980a(5) =3199581a(6) =63999600a(7) =1279991601a(8) =25599991620a(9) =511999832020
External references
- oeis: A221584