Number of cyclic arrangements (up to direction) of {0,1,...,n-1} such that the sum of any two neighbors is a prime.
A242527
Number of cyclic arrangements (up to direction) of {0,1,...,n-1} such that the sum of any two neighbors is a prime.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =1a(6) =2a(7) =6a(8) =6a(9) =22a(10) =80a(11) =504a(12) =840a(13) =6048a(14) =3888a(15) =37524a(16) =72976a(17) =961776a(18) =661016a(19) =11533030a(20) =7544366a(21) =133552142a(22) =208815294a(23) =5469236592a(24) =6429567323a(25) =153819905698a(26) =182409170334
External references
- oeis: A242527