A226890 - cp's OEIS frontend

A226890 E.g.f.: exp( Sum_{n>=1} sigma(n,n) * x^(n^2) / n^n ).

n	a(n)
0	1
1	1
2	1
3	1
4	31
5	151
6	451
7	1051
8	33601
9	663601
10	5187001
11	25905001
12	254322751
13	10408719751
14	128046088171
15	920598820051
16	29249420054401
17	723848667813601
18	12441294278905201
19	138598703861148241
20	4406639731521827551
21	93453608310743628151
22	1932981245635597160851
23	27744052310106087405451

[1, 1, 1, 1, 31, 151, 451, 1051, 33601, 663601, 5187001, 25905001, 254322751, 10408719751, 128046088171, 920598820051, 29249420054401, 723848667813601, 12441294278905201, 138598703861148241, 4406639731521827551, 93453608310743628151, 1932981245635597160851, 27744052310106087405451]

cp's OEIS Frontend

A226890 E.g.f.: exp( Sum_{n>=1} sigma(n,n) * x^(n^2) / n^n ).

Table of values

List of values