Number of permutations of length n with exactly 4 occurrences of the pattern 2-13.
A120812
Number of permutations of length n with exactly 4 occurrences of the pattern 2-13.
Terms
- a(0) =1a(1) =44a(2) =700a(3) =7460a(4) =63648a(5) =470934a(6) =3155691a(7) =19660630a(8) =115855025a(9) =653392740a(10) =3556757490a(11) =18805317960a(12) =97034823600a(13) =490465092600
External references
- oeis: A120812