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 | 252 |
| 3 | 7337 |
| 4 | 84575 |
| 5 | 576080 |
| 6 | 2795121 |
| 7 | 10700382 |
| 8 | 34388362 |
| 9 | 96606475 |
| 10 | 243939410 |
| 11 | 564840991 |
| 12 | 1217275137 |
| 13 | 2469392562 |
| 14 | 4757404575 |
| 15 | 8765621740 |
| 16 | 15534503236 |
| 17 | 26603512517 |
| 18 | 44196596312 |
| 19 | 71459197125 |
| 20 | 112756874195 |
| 21 | 174046844356 |
| 22 | 263335062397 |
| 23 | 391232840362 |
| 24 | 571628456750 |
| 25 | 822490729775 |