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 | 223 |
| 4 | 1311 |
| 5 | 7807 |
| 6 | 46719 |
| 7 | 280063 |
| 8 | 1679871 |
| 9 | 10078207 |
| 10 | 60467199 |
| 11 | 362799103 |
| 12 | 2176786431 |
| 13 | 13060702207 |
| 14 | 78364180479 |
| 15 | 470185017343 |
| 16 | 2821109972991 |
| 17 | 16926659575807 |
| 18 | 101559956930559 |
| 19 | 609359740534783 |
| 20 | 3656158441111551 |
| 21 | 21936950642475007 |
| 22 | 131621703846461439 |