A354734 - cp's OEIS frontend

A354734 a(0) = a(1) = 1; a(n) = 3 * Sum_{k=0..n-2} a(k) * a(n-k-2).

n	a(n)
0	1
1	1
2	3
3	6
4	21
5	54
6	189
7	558
8	1944
9	6210
10	21681
11	72576
12	254988
13	878850
14	3112101
15	10935000
16	39030660
17	139001346
18	499808232
19	1797731496
20	6506661798
21	23583173328
22	85847830965
23	313063862436
24	1145325387114
25	4197826175634
26	15424343762184
27	56774049331356
28	209400739623054

[1, 1, 3, 6, 21, 54, 189, 558, 1944, 6210, 21681, 72576, 254988, 878850, 3112101, 10935000, 39030660, 139001346, 499808232, 1797731496, 6506661798, 23583173328, 85847830965, 313063862436, 1145325387114, 4197826175634, 15424343762184, 56774049331356, 209400739623054]

cp's OEIS Frontend

A354734 a(0) = a(1) = 1; a(n) = 3 * Sum_{k=0..n-2} a(k) * a(n-k-2).

Table of values

List of values