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) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 1 |
| 4 | 65 |
| 5 | 326 |
| 6 | 1957 |
| 7 | 137 |
| 8 | 109601 |
| 9 | 986410 |
| 10 | 9864101 |
| 11 | 27126278 |
| 12 | 7704505 |
| 13 | 16926797486 |
| 14 | 236975164805 |
| 15 | 888656868019 |
| 16 | 56874039553217 |
| 17 | 966858672404690 |
| 18 | 17403456103284421 |
| 19 | 826664164906010 |
| 20 | 6613313319248080001 |
| 21 | 138879579704209680022 |
| 22 | 3055350753492612960485 |