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 | 12 |
| 2 | 1428 |
| 3 | 246675 |
| 4 | 50067108 |
| 5 | 11124755664 |
| 6 | 2619631042665 |
| 7 | 642312451217745 |
| 8 | 162250238001816900 |
| 9 | 41932353590942745504 |
| 10 | 11034966795189838872624 |
| 11 | 2946924270225408943665279 |
| 12 | 796607831560617902288322405 |
| 13 | 217550867863011281855594752680 |