A318109 - cp's OEIS frontend

A318109 a(n) = Sum_{k=0..n} (3n-2k)!/((n-k)!^3k!)(-2)^k.

n	a(n)
0	1
1	4
2	46
3	652
4	10186
5	168304
6	2884456
7	50723824
8	909192538
9	16538659384
10	304391739796
11	5655971294824
12	105929883322576
13	1997228410630912
14	37871584674309376
15	721672204654077952
16	13811327854028171098
17	265324110145941691912
18	5114208160758838538044
19	98874597697991698311832
20	1916741738060370782929036

[1, 4, 46, 652, 10186, 168304, 2884456, 50723824, 909192538, 16538659384, 304391739796, 5655971294824, 105929883322576, 1997228410630912, 37871584674309376, 721672204654077952, 13811327854028171098, 265324110145941691912, 5114208160758838538044, 98874597697991698311832, 1916741738060370782929036]

cp's OEIS Frontend

A318109 a(n) = Sum_{k=0..n} (3n-2k)!/((n-k)!^3k!)(-2)^k.

Table of values

List of values

cp's OEIS Frontend

A318109 a(n) = Sum_{k=0..n} (3*n-2*k)!/((n-k)!^3*k!)*(-2)^k.

Table of values

List of values

A318109 a(n) = Sum_{k=0..n} (3n-2k)!/((n-k)!^3k!)(-2)^k.