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 | 1 |
| 2 | 31 |
| 3 | 211 |
| 4 | 1291 |
| 5 | 7771 |
| 6 | 46651 |
| 7 | 279931 |
| 8 | 1679611 |
| 9 | 10077691 |
| 10 | 60466171 |
| 11 | 362797051 |
| 12 | 2176782331 |
| 13 | 13060694011 |
| 14 | 78364164091 |
| 15 | 470184984571 |
| 16 | 2821109907451 |
| 17 | 16926659444731 |
| 18 | 101559956668411 |
| 19 | 609359740010491 |
| 20 | 3656158440062971 |