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.

A333983 a(0) = 0; a(n) = 4^(n-1) + (1/n) * Sum_{k=1..n-1} binomial(n,k)^2 * 4^(k-1) * (n-k) * a(n-k).

Table of values

n a(n)
0 0
1 1
2 6
3 64
4 1328
5 46336
6 2423040
7 177379840
8 17314109440
9 2172895068160
10 340868882825216
11 65356107645583360
12 15037174515952517120
13 4088810357694136320000
14 1297103066111891262668800
15 474788193071044243776077824
16 198617395218460028950533898240
17 94165608216423156721014443868160

List of values

[0, 1, 6, 64, 1328, 46336, 2423040, 177379840, 17314109440, 2172895068160, 340868882825216, 65356107645583360, 15037174515952517120, 4088810357694136320000, 1297103066111891262668800, 474788193071044243776077824, 198617395218460028950533898240, 94165608216423156721014443868160]