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 | 2 |
| 3 | 4 |
| 4 | 12 |
| 5 | 37 |
| 6 | 162 |
| 7 | 738 |
| 8 | 3928 |
| 9 | 22436 |
| 10 | 138716 |
| 11 | 911529 |
| 12 | 6339770 |
| 13 | 46336941 |
| 14 | 354453138 |
| 15 | 2826472249 |
| 16 | 23423053967 |
| 17 | 201179882629 |
| 18 | 1786791372857 |
| 19 | 16377359709120 |
| 20 | 154644691266520 |
| 21 | 1502016160624186 |
| 22 | 14985219655673207 |
| 23 | 153377735526218010 |
| 24 | 1608741204839374373 |