Number of cyclic arrangements of S={1,2,...,n} such that the difference of any two neighbors is not coprime to their sum.
A242534
Number of cyclic arrangements of S={1,2,...,n} such that the difference of any two neighbors is not coprime to their sum.
Terms
- a(0) =1a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =72a(10) =288a(11) =3600a(12) =17856a(13) =174528a(14) =2540160a(15) =14768640a(16) =101030400a(17) =1458266112a(18) =11316188160a(19) =140951577600
External references
- oeis: A242534