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.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 21 |
| 3 | 77 |
| 4 | 277 |
| 5 | 1005 |
| 6 | 3693 |
| 7 | 13725 |
| 8 | 51477 |
| 9 | 194477 |
| 10 | 739021 |
| 11 | 2821725 |
| 12 | 10816621 |
| 13 | 41602397 |
| 14 | 160466397 |
| 15 | 620470077 |
| 16 | 2404321557 |
| 17 | 9334424877 |
| 18 | 36300541197 |
| 19 | 141381055197 |
| 20 | 551386115277 |
| 21 | 2153031497757 |
| 22 | 8416395854877 |
| 23 | 32933722910397 |
| 24 | 128990414732397 |
| 25 | 505642425751005 |
| 26 | 1983674131792413 |