A371755 - cp's OEIS frontend

A371755 a(n) = Sum_{k=0..floor(n/3)} binomial(4n-2k,n-3*k).

n	a(n)
0	1
1	4
2	28
3	221
4	1834
5	15657
6	136137
7	1199014
8	10661184
9	95493145
10	860339723
11	7788028028
12	70777321331
13	645359630071
14	5901209474518
15	54093485799726
16	496910913391428
17	4573312196055502
18	42160889572810597
19	389258294230352460
20	3598732127428879981

[1, 4, 28, 221, 1834, 15657, 136137, 1199014, 10661184, 95493145, 860339723, 7788028028, 70777321331, 645359630071, 5901209474518, 54093485799726, 496910913391428, 4573312196055502, 42160889572810597, 389258294230352460, 3598732127428879981]

cp's OEIS Frontend

A371755 a(n) = Sum_{k=0..floor(n/3)} binomial(4n-2k,n-3*k).

Table of values

List of values

cp's OEIS Frontend

A371755 a(n) = Sum_{k=0..floor(n/3)} binomial(4*n-2*k,n-3*k).

Table of values

List of values

A371755 a(n) = Sum_{k=0..floor(n/3)} binomial(4n-2k,n-3*k).