Number of permutations of 1..n with no three elements in correct or reverse order.

A095816

Number of permutations of 1..n with no three elements in correct or reverse order.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =18a(5) =92a(6) =570a(7) =4082a(8) =33292a(9) =304490a(10) =3086890a(11) =34357812a(12) =416526730a(13) =5463479106a(14) =77094352076

External references