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) |
|---|---|
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 30 |
| 6 | 134 |
| 7 | 714 |
| 8 | 4462 |
| 9 | 32126 |
| 10 | 262362 |
| 11 | 2398738 |
| 12 | 24287222 |
| 13 | 269858022 |
| 14 | 3265282066 |
| 15 | 42745510682 |
| 16 | 601999275438 |
| 17 | 9076296768142 |
| 18 | 145869055202282 |
| 19 | 2489498542118946 |