898560
domain: N
Appears in sequences
- Number of double-free subsets of {1, 2, ..., n}.at n=24A050291
- Expansion of a Schwarzian ({f_{27|3}, tau} / (4*Pi)^2) in powers of q^3.at n=24A062248
- Numbers k such that S(S(k))=k, with S(n)=sigma(n)/4: 1/4-sociable numbers of order 1 or 2.at n=3A113286
- Triangle read by rows: number of extensional acyclic digraphs on n labeled nodes with k sources.at n=7A182162
- First column of A182162.at n=5A182163
- Largest members of fully k-sociable cycles of order r.at n=28A183023
- Expansion of e.g.f. 1 / (1 - x * cos(x)).at n=10A352252
- a(n) = det(M) where M is an n X n matrix with M[i,j] = i^j*(i-j).at n=5A360067