Number of permutations of [n] with exactly two (possibly overlapping) occurrences of the generalized pattern 23-1.

A264461

Number of permutations of [n] with exactly two (possibly overlapping) occurrences of the generalized pattern 23-1.

Terms

    a(0) =3a(1) =23a(2) =152a(3) =984a(4) =6460a(5) =43626a(6) =304939a(7) =2211467a(8) =16649780a(9) =130097338a(10) =1054226016a(11) =8850736900a(12) =76901730751a(13) =690749091147

External references