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) |
|---|---|
| 2 | 1 |
| 3 | 7 |
| 4 | 37 |
| 5 | 177 |
| 6 | 808 |
| 7 | 3596 |
| 8 | 15764 |
| 9 | 68446 |
| 10 | 295294 |
| 11 | 1268356 |
| 12 | 5430734 |
| 13 | 23199304 |
| 14 | 98933705 |
| 15 | 421352919 |
| 16 | 1792709561 |
| 17 | 7621345733 |
| 18 | 32380443643 |
| 19 | 137504761035 |
| 20 | 583684770103 |
| 21 | 2476836131227 |
| 22 | 10507517431481 |
| 23 | 44566369523517 |
| 24 | 188988331406117 |