A362173 - cp's OEIS frontend

A362173 a(n) = n! * Sum_{k=0..floor(n/3)} (n/6)^k * binomial(n-2k,k)/(n-2k)!.

n	a(n)
0	1
1	1
2	1
3	4
4	17
5	51
6	481
7	3676
8	18369
9	272917
10	3011201
11	21058236
12	427112401
13	6160655359
14	55380250017
15	1423658493076
16	25361574327041
17	278603741558601
18	8673295084155649
19	183914415577719892
20	2387417408385462801
21	87273239189497636171
22	2146479566819857007201

[1, 1, 1, 4, 17, 51, 481, 3676, 18369, 272917, 3011201, 21058236, 427112401, 6160655359, 55380250017, 1423658493076, 25361574327041, 278603741558601, 8673295084155649, 183914415577719892, 2387417408385462801, 87273239189497636171, 2146479566819857007201]

cp's OEIS Frontend

A362173 a(n) = n! * Sum_{k=0..floor(n/3)} (n/6)^k * binomial(n-2k,k)/(n-2k)!.

Table of values

List of values

cp's OEIS Frontend

A362173 a(n) = n! * Sum_{k=0..floor(n/3)} (n/6)^k * binomial(n-2*k,k)/(n-2*k)!.

Table of values

List of values

A362173 a(n) = n! * Sum_{k=0..floor(n/3)} (n/6)^k * binomial(n-2k,k)/(n-2k)!.