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 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
| 6 | 146 |
| 7 | 4207 |
| 8 | 26329 |
| 9 | 257721 |
| 10 | 3556495 |
| 11 | 42685181 |
| 12 | 631230381 |
| 13 | 9409600499 |
| 14 | 142557084957 |
| 15 | 2781352245050 |
| 16 | 52598395446786 |
| 17 | 950288577530017 |
| 18 | 20768368026768594 |
| 19 | 448759012546543804 |
| 20 | 9652848877533217174 |
| 21 | 235179507693424886403 |
| 22 | 5756272592837812726164 |
| 23 | 140920987987840184113287 |