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 | 0 |
| 1 | 1 |
| 2 | 34 |
| 3 | 792 |
| 4 | 10688 |
| 5 | 90005 |
| 6 | 533358 |
| 7 | 2437848 |
| 8 | 9156288 |
| 9 | 29522961 |
| 10 | 84293770 |
| 11 | 217993600 |
| 12 | 519341472 |
| 13 | 1154658869 |
| 14 | 2420188694 |
| 15 | 4821091920 |
| 16 | 9187076352 |
| 17 | 16837177281 |
| 18 | 29809183410 |
| 19 | 51172613512 |
| 20 | 85448030080 |
| 21 | 139159855989 |
| 22 | 221554769150 |
| 23 | 345523218536 |
| 24 | 528767663040 |