The number of collections F of subsets of {1,2,...,n} such that the union of F is not an element of F.

A246537

The number of collections F of subsets of {1,2,...,n} such that the union of F is not an element of F.

Terms

    a(0) =1a(1) =1a(2) =3a(3) =97a(4) =32199a(5) =2147318437

External references