The number of permutations p of {1,...,n} such that |p(i)-p(i+1)| is in {3,4,5} for all i from 1 to n-1.
A174707
The number of permutations p of {1,...,n} such that |p(i)-p(i+1)| is in {3,4,5} for all i from 1 to n-1.
Terms
- a(0) =1a(1) =0a(2) =0a(3) =0a(4) =0a(5) =2a(6) =28a(7) =144a(8) =292a(9) =272a(10) =160a(11) =272a(12) =844a(13) =3888a(14) =15830a(15) =49080a(16) =113468a(17) =208224a(18) =352112a(19) =662810a(20) =1497286a(21) =3853054a(22) =10238142a(23) =25892602a(24) =60223752a(25) =130042700a(26) =271136524a(27) =572265830a(28) =1258121046a(29) =2878870324
External references
- oeis: A174707