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 | 1 |
| 2 | 6 |
| 3 | 69 |
| 4 | 812 |
| 5 | 10471 |
| 6 | 141702 |
| 7 | 1997687 |
| 8 | 28988856 |
| 9 | 430321563 |
| 10 | 6503342378 |
| 11 | 99726673129 |
| 12 | 1547847703500 |
| 13 | 24269405074739 |
| 14 | 383846166714410 |
| 15 | 6116574500850339 |
| 16 | 98106248277869040 |
| 17 | 1582638261961640246 |
| 18 | 25661404527359789034 |
| 19 | 417980115131315136399 |
| 20 | 6836064539918615002932 |