A303284 - cp's OEIS frontend

A303284 Number of permutations p of [n] such that the sequence of ascents and descents of 0p or of 0p0 (if n is odd) forms a Dyck path.

n	a(n)
0	1
1	1
2	1
3	4
4	8
5	60
6	172
7	1974
8	7296
9	114972
10	518324
11	10490392
12	55717312
13	1384890104
14	8460090160
15	250150900354
16	1726791794432
17	59317740001132
18	456440969661508
19	17886770092245360
20	151770739970889792
21	6687689652133397064
22	62022635037246022000
23	3037468107154650475868

[1, 1, 1, 4, 8, 60, 172, 1974, 7296, 114972, 518324, 10490392, 55717312, 1384890104, 8460090160, 250150900354, 1726791794432, 59317740001132, 456440969661508, 17886770092245360, 151770739970889792, 6687689652133397064, 62022635037246022000, 3037468107154650475868]

cp's OEIS Frontend

A303284 Number of permutations p of [n] such that the sequence of ascents and descents of 0p or of 0p0 (if n is odd) forms a Dyck path.

Table of values

List of values