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 | 96 |
| 3 | 616 |
| 4 | 3444 |
| 5 | 17472 |
| 6 | 82432 |
| 7 | 367488 |
| 8 | 1565280 |
| 9 | 6421376 |
| 10 | 25525248 |
| 11 | 98773248 |
| 12 | 373450112 |
| 13 | 1383674880 |
| 14 | 5036089344 |
| 15 | 18041821184 |
| 16 | 63727070976 |
| 17 | 222249968640 |
| 18 | 766234140672 |
| 19 | 2614196680704 |
| 20 | 8834194123776 |