Number of cyclic arrangements of S={1,2,...,2n} such that the difference of any two neighbors is coprime to their sum.

A242533

Number of cyclic arrangements of S={1,2,...,2n} such that the difference of any two neighbors is coprime to their sum.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =36a(4) =288a(5) =3888a(6) =200448a(7) =4257792a(8) =139511808a(9) =11813990400a(10) =532754620416

External references