Number of degree-2n permutations such that number of cycles of size 2k-1 is even (or zero) for every k.

A130276

Number of degree-2n permutations such that number of cycles of size 2k-1 is even (or zero) for every k.

Terms

    a(0) =1a(1) =2a(2) =16a(3) =416a(4) =20224a(5) =1645312a(6) =196388864a(7) =33279311872

External references