658409472000
domain: N
Appears in sequences
- a(n+1) = a(n)/n! if n! divides a(n) else a(n)*n!.at n=12A008338
- a(n) = n!*(n+1)!/2.at n=8A010796
- A092186(n)/2.at n=17A092187
- Number of circular permutations of the multiset {1,1,2,2,...,n,n} (up to rotations) with odd distances between equal elements.at n=9A137730
- Number of permutations of {1,2,3,...,n} such that no even numbers are adjacent.at n=17A258213
- Number of even parity alternating permutations of [1..n] starting with an odd integer.at n=19A364849