Number of degree-2n permutations such that number of cycles of size 2k is odd (or zero) and number of cycles of size 2k-1 is even (or zero), for every k.
A131525
Number of degree-2n permutations such that number of cycles of size 2k is odd (or zero) and number of cycles of size 2k-1 is even (or zero), for every k.
Terms
- a(0) =1a(1) =2a(2) =13a(3) =371a(4) =17389a(5) =1369057a(6) =168362459a(7) =28396593031
External references
- oeis: A131525