A371854 - cp's OEIS frontend

A371854 a(n) = Sum_{k=0..floor(n/3)} binomial(2n-k+2,n-3k).

n	a(n)
0	1
1	4
2	15
3	57
4	219
5	847
6	3290
7	12819
8	50066
9	195909
10	767790
11	3013002
12	11837043
13	46548919
14	183209125
15	721628692
16	2844297119
17	11217639757
18	44265835891
19	174765349896
20	690308413773
21	2727823240762
22	10783518961394
23	42644560775835
24	168699835910561
25	667580653569309

[1, 4, 15, 57, 219, 847, 3290, 12819, 50066, 195909, 767790, 3013002, 11837043, 46548919, 183209125, 721628692, 2844297119, 11217639757, 44265835891, 174765349896, 690308413773, 2727823240762, 10783518961394, 42644560775835, 168699835910561, 667580653569309]

cp's OEIS Frontend

A371854 a(n) = Sum_{k=0..floor(n/3)} binomial(2n-k+2,n-3k).

Table of values

List of values

cp's OEIS Frontend

A371854 a(n) = Sum_{k=0..floor(n/3)} binomial(2*n-k+2,n-3*k).

Table of values

List of values

A371854 a(n) = Sum_{k=0..floor(n/3)} binomial(2n-k+2,n-3k).