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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 10 |
| 6 | 29 |
| 7 | 113 |
| 8 | 368 |
| 9 | 1316 |
| 10 | 4490 |
| 11 | 15907 |
| 12 | 55866 |
| 13 | 199550 |
| 14 | 714601 |
| 15 | 2583575 |
| 16 | 9385280 |
| 17 | 34311304 |
| 18 | 126018592 |
| 19 | 465044951 |
| 20 | 1722987050 |
| 21 | 6407739430 |
| 22 | 23909854891 |
| 23 | 89493459541 |
| 24 | 335911158480 |
| 25 | 1264104712300 |