A121485 - cp's OEIS frontend

A121485 Number of nondecreasing Dyck paths of semilength n and having no peaks at even level (n>=0). A nondecreasing Dyck path is a Dyck path for which the sequence of the altitudes of the valleys is nondecreasing.

n	a(n)
1	1
2	1
3	2
4	4
5	8
6	16
7	33
8	66
9	136
10	274
11	562
12	1138
13	2327
14	4725
15	9645
16	19613
17	39997
18	81397
19	165906
20	337773
21	688260
22	1401565
23	2855432
24	5815477
25	11846941
26	24129498
27	49152840
28	100116607
29	203936639
30	415394872
31	846143795
32	1723513075
33	3510704795

[1, 1, 2, 4, 8, 16, 33, 66, 136, 274, 562, 1138, 2327, 4725, 9645, 19613, 39997, 81397, 165906, 337773, 688260, 1401565, 2855432, 5815477, 11846941, 24129498, 49152840, 100116607, 203936639, 415394872, 846143795, 1723513075, 3510704795]

cp's OEIS Frontend

A121485 Number of nondecreasing Dyck paths of semilength n and having no peaks at even level (n>=0). A nondecreasing Dyck path is a Dyck path for which the sequence of the altitudes of the valleys is nondecreasing.

Table of values

List of values