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) |
|---|---|
| 1 | 8 |
| 2 | 20 |
| 3 | 84 |
| 4 | 500 |
| 5 | 3540 |
| 6 | 26996 |
| 7 | 212052 |
| 8 | 1684724 |
| 9 | 13442772 |
| 10 | 107437172 |
| 11 | 859182420 |
| 12 | 6872514548 |
| 13 | 54977282004 |
| 14 | 439809752948 |
| 15 | 3518452514388 |
| 16 | 28147543587572 |
| 17 | 225180119118036 |
| 18 | 1801440264196724 |
| 19 | 14411520047331156 |
| 20 | 115292154179921396 |
| 21 | 922337214843187668 |
| 22 | 7378697662956950900 |
| 23 | 59029581136289955924 |