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 | 37 |
| 3 | 259 |
| 4 | 1297 |
| 5 | 9079 |
| 6 | 47989 |
| 7 | 335923 |
| 8 | 1679617 |
| 9 | 11757319 |
| 10 | 62145829 |
| 11 | 435020803 |
| 12 | 2178463249 |
| 13 | 15249242743 |
| 14 | 80603140213 |
| 15 | 564221981491 |
| 16 | 2821109907457 |
| 17 | 19747769352199 |
| 18 | 104381066575909 |
| 19 | 730667466031363 |
| 20 | 3658979549971729 |