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 | 7 |
| 2 | 39 |
| 3 | 193 |
| 4 | 886 |
| 5 | 3858 |
| 6 | 16146 |
| 7 | 65502 |
| 8 | 259119 |
| 9 | 1003833 |
| 10 | 3820689 |
| 11 | 14322663 |
| 12 | 52986636 |
| 13 | 193759452 |
| 14 | 701265924 |
| 15 | 2514778812 |
| 16 | 8943620589 |
| 17 | 31569189723 |
| 18 | 110673119691 |
| 19 | 385569479997 |
| 20 | 1335567565746 |
| 21 | 4601780568342 |
| 22 | 15778086835014 |
| 23 | 53852222811978 |
| 24 | 183024799992891 |
| 25 | 619577180566893 |