cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A337053 a(n) = exp(2) * Sum_{i>=0} Sum_{j>=0} (-1)^(i+j) * (i*j)^n / (i! * j!).

Table of values

n a(n)
0 1
1 1
2 0
3 1
4 1
5 4
6 81
7 81
8 2500
9 71289
10 170569
11 4752400
12 314388361
13 2553584089
14 12138750976
15 3868290439209
16 98777141491561
17 74627448683524
18 77548359598953721
19 6456459980629467081
20 96370747288471888164
21 738333256838429983201
22 526354651474052521626801

List of values

[1, 1, 0, 1, 1, 4, 81, 81, 2500, 71289, 170569, 4752400, 314388361, 2553584089, 12138750976, 3868290439209, 98777141491561, 74627448683524, 77548359598953721, 6456459980629467081, 96370747288471888164, 738333256838429983201, 526354651474052521626801]