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 | 9 |
| 2 | 21 |
| 3 | 69 |
| 4 | 129 |
| 5 | 381 |
| 6 | 2271 |
| 7 | 3849 |
| 8 | 3909 |
| 9 | 3921 |
| 10 | 5001 |
| 11 | 5079 |
| 12 | 5169 |
| 13 | 5349 |
| 14 | 7041 |
| 15 | 16251 |
| 16 | 18129 |
| 17 | 18399 |
| 18 | 20481 |
| 19 | 22569 |
| 20 | 22641 |
| 21 | 22719 |
| 22 | 22809 |
| 23 | 28029 |
| 24 | 32259 |
| 25 | 35151 |
| 26 | 38559 |
| 27 | 39021 |
| 28 | 39441 |
| 29 | 39981 |
| 30 | 41079 |
| 31 | 42459 |
| 32 | 48759 |
| 33 | 48819 |
| 34 | 49431 |
| 35 | 50649 |
| 36 | 61629 |
| 37 | 67929 |