A045994 - cp's OEIS frontend

A045994 a(0)=1, a(n) = M(n) + Sum_{k=1..n-1} M(k)*a(n-k-1), where M(n) are the Motzkin numbers (A001006).

n	a(n)
0	1
1	1
2	3
3	7
4	18
5	47
6	125
7	337
8	918
9	2522
10	6977
11	19415
12	54297
13	152507
14	429974
15	1216297
16	3450817
17	9816460
18	27991422
19	79989880
20	229034820
21	656979399
22	1887653560
23	5431969355
24	15653355151
25	45167783715
26	130491471940
27	377426429199

[1, 1, 3, 7, 18, 47, 125, 337, 918, 2522, 6977, 19415, 54297, 152507, 429974, 1216297, 3450817, 9816460, 27991422, 79989880, 229034820, 656979399, 1887653560, 5431969355, 15653355151, 45167783715, 130491471940, 377426429199]

cp's OEIS Frontend

A045994 a(0)=1, a(n) = M(n) + Sum_{k=1..n-1} M(k)*a(n-k-1), where M(n) are the Motzkin numbers (A001006).

Table of values

List of values