325024572
domain: N
Appears in sequences
- Eulerian version of the Catalan numbers, a(n) = A008292(2*n+1,n+1)/(n+1).at n=6A177042
- Number of permutations p of [n] such that the sequence of ascents and descents of p or of p0 (if n is even) forms a Dyck path.at n=13A303287
- Number T(n,k) of permutations p of [n] with exactly k descents such that the up-down signature of p has nonnegative partial sums; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-1)/2)), read by rows.at n=49A321280