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 | 7 |
| 1 | 55 |
| 2 | 391 |
| 3 | 2743 |
| 4 | 19207 |
| 5 | 134455 |
| 6 | 941191 |
| 7 | 6588343 |
| 8 | 46118407 |
| 9 | 322828855 |
| 10 | 2259801991 |
| 11 | 15818613943 |
| 12 | 110730297607 |
| 13 | 775112083255 |
| 14 | 5425784582791 |
| 15 | 37980492079543 |
| 16 | 265863444556807 |
| 17 | 1861044111897655 |
| 18 | 13027308783283591 |
| 19 | 91191161482985143 |