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.

A220266 G.f.: Sum_{n>=1} (2*(1+x)^n - 1) * ((1+x)^n - 1)^(n-1).

Table of values

n a(n)
0 1
1 4
2 18
3 144
4 1604
5 22944
6 400624
7 8259680
8 196358760
9 5287879092
10 159094582274
11 5288950560768
12 192527721428892
13 7616404083126180
14 325361411700398046
15 14926683772801407168
16 731947910056020737036
17 38204289826040411251632
18 2114787166947079113869760

List of values

[1, 4, 18, 144, 1604, 22944, 400624, 8259680, 196358760, 5287879092, 159094582274, 5288950560768, 192527721428892, 7616404083126180, 325361411700398046, 14926683772801407168, 731947910056020737036, 38204289826040411251632, 2114787166947079113869760]