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 | 17 |
| 3 | 49 |
| 4 | 73 |
| 5 | 289 |
| 6 | 307 |
| 7 | 1297 |
| 8 | 3013 |
| 9 | 8959 |
| 10 | 664831 |
| 11 | 1399549 |
| 12 | 5122561 |
| 13 | 8515193 |
| 14 | 11012719 |
| 15 | 65998063 |
| 16 | 145256891 |
| 17 | 294363959 |
| 18 | 734746001 |
| 19 | 1255837139 |
| 20 | 1454498597 |
| 21 | 5287956641 |