Number of permutations p of [n] having at least one index i with |p(i)-i| = 2.
A306524
Number of permutations p of [n] having at least one index i with |p(i)-i| = 2.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =3a(4) =15a(5) =86a(6) =544a(7) =3934a(8) =32079a(9) =292509a(10) =2952702a(11) =32712087a(12) =394749367a(13) =5155010088a(14) =72440184064
External references
- oeis: A306524