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 | 2 |
| 3 | 3 |
| 4 | 12 |
| 5 | 23 |
| 6 | 84 |
| 7 | 204 |
| 8 | 830 |
| 9 | 2940 |
| 10 | 13397 |
| 11 | 58794 |
| 12 | 283132 |
| 13 | 1377302 |
| 14 | 7087164 |
| 15 | 37654377 |
| 16 | 209943842 |
| 17 | 1226495407 |
| 18 | 7579549767 |
| 19 | 49541194089 |
| 20 | 341964495985 |
| 21 | 2476907459261 |
| 22 | 18703210872343 |
| 23 | 146284738788714 |
| 24 | 1179199861398539 |
| 25 | 9760466433602510 |
| 26 | 82758834102114911 |
| 27 | 717807201648148643 |