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 | 65 |
| 3 | 89 |
| 4 | 1293 |
| 5 | 4853 |
| 6 | 34441 |
| 7 | 163043 |
| 8 | 915663 |
| 9 | 4537317 |
| 10 | 23671551 |
| 11 | 118358549 |
| 12 | 601565301 |
| 13 | 3011330309 |
| 14 | 15155615651 |
| 15 | 75845220727 |
| 16 | 380253505733 |
| 17 | 1902264449049 |
| 18 | 9522274036139 |
| 19 | 47624961772074 |
| 20 | 238244610944161 |
| 21 | 1191402062810086 |