Number of cyclic arrangements of S={1,2,...,n} such that the difference between any two neighbors is at most 4.

A242526

Number of cyclic arrangements of S={1,2,...,n} such that the difference between any two neighbors is at most 4.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =3a(4) =12a(5) =36a(6) =90a(7) =214a(8) =521a(9) =1335a(10) =3473a(11) =9016a(12) =23220a(13) =59428a(14) =152052a(15) =389636a(16) =999776a(17) =2566517a(18) =6586825a(19) =16899574a(20) =43352560a(21) =111213798a(22) =285319258a(23) =732016006a(24) =1878072638a(25) =4818362046a(26) =12361809384a(27) =31714901077a(28) =81366445061a(29) =208750870961

External references