Number of permutations of length n such that at least one absolute difference between consecutive elements has a distinct partner.
A084894
Number of permutations of length n such that at least one absolute difference between consecutive elements has a distinct partner.
Terms
- a(0) =0a(1) =0a(2) =2a(3) =20a(4) =112a(5) =696a(6) =5008a(7) =40280a(8) =362760a(9) =3628504a(10) =39916152a(11) =479000272a(12) =6227017600a(13) =87178281288
External references
- oeis: A084894