A336804 - cp's OEIS frontend

A336804 a(n) = (n!)^2 * Sum_{k=0..n} 2^(n-k) / (k!)^2.

n	a(n)
0	1
1	3
2	25
3	451
4	14433
5	721651
6	51958873
7	5091969555
8	651772103041
9	105587080692643
10	21117416138528601
11	5110414705523921443
12	1471799435190889375585
13	497468209094520608947731
14	195007537965052078707510553
15	87753392084273435418379748851
16	44929736747147998934210431411713

[1, 3, 25, 451, 14433, 721651, 51958873, 5091969555, 651772103041, 105587080692643, 21117416138528601, 5110414705523921443, 1471799435190889375585, 497468209094520608947731, 195007537965052078707510553, 87753392084273435418379748851, 44929736747147998934210431411713]

cp's OEIS Frontend

A336804 a(n) = (n!)^2 * Sum_{k=0..n} 2^(n-k) / (k!)^2.

Table of values

List of values