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 | 2 |
| 2 | 5 |
| 3 | 16 |
| 4 | 53 |
| 5 | 186 |
| 6 | 665 |
| 7 | 2430 |
| 8 | 8981 |
| 9 | 33556 |
| 10 | 126300 |
| 11 | 478468 |
| 12 | 1821677 |
| 13 | 6965726 |
| 14 | 26730639 |
| 15 | 102895388 |
| 16 | 397130997 |
| 17 | 1536321264 |
| 18 | 5955477230 |
| 19 | 23128018490 |
| 20 | 89962619148 |
| 21 | 350442078972 |
| 22 | 1366907765382 |
| 23 | 5337995113404 |
| 24 | 20868301796085 |