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 | 20 |
| 2 | 21 |
| 3 | 1555 |
| 4 | 889 |
| 5 | 253 |
| 6 | 2041 |
| 7 | 5846759 |
| 8 | 148305659 |
| 9 | 1081 |
| 10 | 279241 |
| 11 | 9641 |
| 12 | 950123 |
| 13 | 33661 |
| 14 | 63213709997 |
| 15 | 583223 |
| 16 | 3775349 |
| 17 | 72707647 |
| 18 | 149070763 |
| 19 | 196932497 |
| 20 | 5091481 |
| 21 | 25760459 |
| 22 | 14307947980741 |
| 23 | 13861 |
| 24 | 9362711 |
| 25 | 376457 |
| 26 | 132766545553 |
| 27 | 63757 |