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 | 10 |
| 2 | 670 |
| 3 | 55252 |
| 4 | 4816030 |
| 5 | 432457640 |
| 6 | 39581170420 |
| 7 | 3671331273480 |
| 8 | 343900019857310 |
| 9 | 32458256583753952 |
| 10 | 3081918923741896840 |
| 11 | 294056694657804068000 |
| 12 | 28170312778225750242100 |