Number of permutations p of [n] such that the up-down signature of 0,p has nonnegative partial sums.
A258830
Number of permutations p of [n] such that the up-down signature of 0,p has nonnegative partial sums.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =20a(5) =87a(6) =522a(7) =3271a(8) =26168a(9) =214955a(10) =2149550a(11) =21881103a(12) =262573236a(13) =3191361201a(14) =44679056814a(15) =631546127049
External references
- oeis: A258830