Number of endofunctions on [n] whose cycle lengths are triangular numbers.

A305824

Number of endofunctions on [n] whose cycle lengths are triangular numbers.

Terms

    a(0) =1a(1) =1a(2) =3a(3) =18a(4) =157a(5) =1776a(6) =24807a(7) =413344a(8) =8004537a(9) =176630400a(10) =4374300331a(11) =120136735104

External references