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 | 2 |
| 2 | 8 |
| 3 | 52 |
| 4 | 376 |
| 5 | 2998 |
| 6 | 25256 |
| 7 | 222128 |
| 8 | 2013680 |
| 9 | 18691522 |
| 10 | 176743160 |
| 11 | 1696546848 |
| 12 | 16488151400 |
| 13 | 161919802562 |
| 14 | 1604274741608 |
| 15 | 16016845623764 |
| 16 | 160977882238968 |
| 17 | 1627406260427490 |
| 18 | 16537733701226936 |