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 | 9 |
| 2 | 126 |
| 3 | 1623 |
| 4 | 20583 |
| 5 | 254493 |
| 6 | 3091803 |
| 7 | 36974025 |
| 8 | 436377771 |
| 9 | 5091463423 |
| 10 | 58811218362 |
| 11 | 673298882775 |
| 12 | 7647050353038 |
| 13 | 86229872235432 |
| 14 | 966019964324004 |
| 15 | 10757807941399023 |
| 16 | 119146632352548516 |
| 17 | 1312935665205028374 |
| 18 | 14400230629085596621 |
| 19 | 157253909597473608945 |