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 | 7 |
| 2 | 84 |
| 3 | 1232 |
| 4 | 20090 |
| 5 | 349860 |
| 6 | 6371764 |
| 7 | 119877472 |
| 8 | 2311664355 |
| 9 | 45448324110 |
| 10 | 907580289616 |
| 11 | 18358110017520 |
| 12 | 375353605696524 |
| 13 | 7744997102466932 |
| 14 | 161070300819384000 |
| 15 | 3372697621463787456 |
| 16 | 71046594621639707245 |
| 17 | 1504569659175026591805 |