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) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 31 |
| 4 | 211 |
| 5 | 2311 |
| 6 | 15017 |
| 7 | 85091 |
| 8 | 1616621 |
| 9 | 22309297 |
| 10 | 3234846617 |
| 11 | 200560490131 |
| 12 | 3710369067407 |
| 13 | 20283350901829 |
| 14 | 872184088778017 |
| 15 | 307444891294245707 |
| 16 | 775932344695001107 |
| 17 | 961380175077106319537 |
| 18 | 19548063559901161830551 |