Number of permutations p of [n] such that the up-down signature of p has nonnegative partial sums with a maximal value of three.
A320977
Number of permutations p of [n] such that the up-down signature of p has nonnegative partial sums with a maximal value of three.
Terms
- a(0) =0a(1) =1a(2) =4a(3) =57a(4) =311a(5) =3857a(6) =27589a(7) =355751a(8) =3185258a(9) =44435241a(10) =479927081a(11) =7311147055a(12) =92603527295
External references
- oeis: A320977