A033297 - cp's OEIS frontend

A033297 Number of ordered rooted trees with n edges such that the rightmost leaf of each subtree is at even level. Equivalently, number of Dyck paths of semilength n with no return descents of odd length.

n	a(n)
2	1
3	1
4	4
5	10
6	32
7	100
8	329
9	1101
10	3761
11	13035
12	45751
13	162261
14	580639
15	2093801
16	7601044
17	27756626
18	101888164
19	375750536
20	1391512654
21	5172607766
22	19293659254
23	72188904386
24	270870709264
25	1019033438060
26	3842912963392

[1, 1, 4, 10, 32, 100, 329, 1101, 3761, 13035, 45751, 162261, 580639, 2093801, 7601044, 27756626, 101888164, 375750536, 1391512654, 5172607766, 19293659254, 72188904386, 270870709264, 1019033438060, 3842912963392]

cp's OEIS Frontend

A033297 Number of ordered rooted trees with n edges such that the rightmost leaf of each subtree is at even level. Equivalently, number of Dyck paths of semilength n with no return descents of odd length.

Table of values

List of values