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 | 2 |
| 2 | 8 |
| 3 | 24 |
| 4 | 86 |
| 5 | 300 |
| 6 | 1096 |
| 7 | 4032 |
| 8 | 15062 |
| 9 | 56684 |
| 10 | 214880 |
| 11 | 818800 |
| 12 | 3133916 |
| 13 | 12038200 |
| 14 | 46384432 |
| 15 | 179193920 |
| 16 | 693849254 |
| 17 | 2691994060 |
| 18 | 10462833808 |
| 19 | 40729251920 |
| 20 | 158772196436 |
| 21 | 619716378280 |
| 22 | 2421643356592 |
| 23 | 9472863484160 |
| 24 | 37090890396284 |