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.

A369088 Expansion of Sum_{n>=0} ( (1+x)^n/(1-x)^n - (1-x)^n/(1+x)^n )^n / 4^n.

Table of values

n a(n)
0 1
1 1
2 4
3 28
4 280
5 3639
6 57996
7 1093795
8 23821104
9 588282772
10 16243898516
11 495894495629
12 16584179388232
13 602955889304341
14 23678788166350620
15 998882687260157956
16 45047554811998482016
17 2162775743390757357579
18 110136661581764181626660
19 5929361362606879245799055
20 336484778280758295928357240

List of values

[1, 1, 4, 28, 280, 3639, 57996, 1093795, 23821104, 588282772, 16243898516, 495894495629, 16584179388232, 602955889304341, 23678788166350620, 998882687260157956, 45047554811998482016, 2162775743390757357579, 110136661581764181626660, 5929361362606879245799055, 336484778280758295928357240]