Number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly 3 local maxima.

A159717

Number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly 3 local maxima.

Terms

    a(0) =0a(1) =0a(2) =6a(3) =1192a(4) =61830a(5) =2150688a(6) =62178928a(7) =1629254640a(8) =40346856234a(9) =965510596600

External references