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 | 1 |
| 2 | 6 |
| 3 | 13 |
| 4 | 71 |
| 5 | 84 |
| 6 | 2087 |
| 7 | 2171 |
| 8 | 12942 |
| 9 | 28055 |
| 10 | 153217 |
| 11 | 181272 |
| 12 | 4503745 |
| 13 | 4685017 |
| 14 | 27928830 |
| 15 | 60542677 |
| 16 | 330642215 |
| 17 | 391184892 |
| 18 | 9719079623 |
| 19 | 10110264515 |
| 20 | 60270402198 |
| 21 | 130651068911 |
| 22 | 713525746753 |
| 23 | 844176815664 |
| 24 | 20973769322689 |
| 25 | 21817946138353 |