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 | 0 |
| 2 | 1 |
| 3 | 12 |
| 4 | 761 |
| 5 | 87336 |
| 6 | 18528505 |
| 7 | 6376563600 |
| 8 | 3338759427857 |
| 9 | 2524750777586976 |
| 10 | 2648982517454387281 |
| 11 | 3733860677541032881728 |
| 12 | 6885982148044369769847497 |
| 13 | 16251753910337100552968630400 |