A386866 - cp's OEIS frontend

A386866 a(n) = Sum_{k=0..n} 2^(n-k) * binomial(3n+2,k) binomial(3*n-k-1,n-k).

n	a(n)
0	1
1	9
2	132
3	2197
4	38649
5	701292
6	12979360
7	243541725
8	4616122851
9	88173726337
10	1694554311888
11	32728267058604
12	634701136059532
13	12351249029265816
14	241061116082196072
15	4716751239386395885
16	92494719333403946583
17	1817328001770278062299
18	35768122814759119268788

[1, 9, 132, 2197, 38649, 701292, 12979360, 243541725, 4616122851, 88173726337, 1694554311888, 32728267058604, 634701136059532, 12351249029265816, 241061116082196072, 4716751239386395885, 92494719333403946583, 1817328001770278062299, 35768122814759119268788]

cp's OEIS Frontend

A386866 a(n) = Sum_{k=0..n} 2^(n-k) * binomial(3n+2,k) binomial(3*n-k-1,n-k).

Table of values

List of values

cp's OEIS Frontend

A386866 a(n) = Sum_{k=0..n} 2^(n-k) * binomial(3*n+2,k) * binomial(3*n-k-1,n-k).

Table of values

List of values

A386866 a(n) = Sum_{k=0..n} 2^(n-k) * binomial(3n+2,k) binomial(3*n-k-1,n-k).