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 | 9 |
| 3 | 20 |
| 4 | 155 |
| 5 | 21 |
| 6 | 7441 |
| 7 | 3224 |
| 8 | 5697 |
| 9 | 3575 |
| 10 | 28523 |
| 11 | 27183 |
| 12 | 70357417 |
| 13 | 4661447 |
| 14 | 386395 |
| 15 | 8959408 |
| 16 | 10028928779 |
| 17 | 525966759 |
| 18 | 1476346738309 |
| 19 | 35051863075 |
| 20 | 847581175 |
| 21 | 709068173 |
| 22 | 62385202783 |
| 23 | 20340152122 |
| 24 | 119483756745025 |
| 25 | 4418168441921 |
| 26 | 311960929172031 |