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 | 4 |
| 3 | 12 |
| 4 | 43 |
| 5 | 142 |
| 6 | 508 |
| 7 | 1781 |
| 8 | 6414 |
| 9 | 23124 |
| 10 | 84296 |
| 11 | 308613 |
| 12 | 1137129 |
| 13 | 4207456 |
| 14 | 15636927 |
| 15 | 58322808 |
| 16 | 218272766 |
| 17 | 819319778 |
| 18 | 3083913810 |
| 19 | 11636761924 |
| 20 | 44010780075 |
| 21 | 166802192488 |
| 22 | 633420816341 |
| 23 | 2409731688860 |
| 24 | 9182826866499 |
| 25 | 35048239457878 |
| 26 | 133965833871427 |