A387622 - cp's OEIS frontend

A387622 a(n) = Sum_{k=0..floor(n/3)} 2^k * binomial(2n-4k,2*k).

n	a(n)
0	1
1	1
2	1
3	3
4	13
5	31
6	61
7	151
8	413
9	1031
10	2445
11	5991
12	15069
13	37447
14	91917
15	226503
16	561373
17	1389735
18	3431501
19	8474983
20	20955229
21	51814407
22	128054029
23	316455559
24	782209629
25	1933537511
26	4779082829
27	11812031271
28	29195752157
29	72164132167
30	178368130061

[1, 1, 1, 3, 13, 31, 61, 151, 413, 1031, 2445, 5991, 15069, 37447, 91917, 226503, 561373, 1389735, 3431501, 8474983, 20955229, 51814407, 128054029, 316455559, 782209629, 1933537511, 4779082829, 11812031271, 29195752157, 72164132167, 178368130061]

cp's OEIS Frontend

A387622 a(n) = Sum_{k=0..floor(n/3)} 2^k * binomial(2n-4k,2*k).

Table of values

List of values

cp's OEIS Frontend

A387622 a(n) = Sum_{k=0..floor(n/3)} 2^k * binomial(2*n-4*k,2*k).

Table of values

List of values

A387622 a(n) = Sum_{k=0..floor(n/3)} 2^k * binomial(2n-4k,2*k).