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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 8 |
| 7 | 17 |
| 8 | 63 |
| 9 | 224 |
| 10 | 1248 |
| 11 | 8218 |
| 12 | 75992 |
| 13 | 906635 |
| 14 | 14447433 |
| 15 | 303100595 |
| 16 | 8415834690 |
| 17 | 309390830222 |
| 18 | 15105805368214 |
| 19 | 982300491033887 |