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 | 8 |
| 3 | 12 |
| 4 | 160 |
| 5 | 740 |
| 6 | 5424 |
| 7 | 37828 |
| 8 | 262784 |
| 9 | 1868868 |
| 10 | 13200880 |
| 11 | 89816804 |
| 12 | 581630592 |
| 13 | 3586158628 |
| 14 | 21162503600 |
| 15 | 120273982980 |
| 16 | 662169758464 |
| 17 | 3549104142980 |
| 18 | 18595278255600 |
| 19 | 95559668680612 |
| 20 | 482965743234560 |
| 21 | 2405973280450404 |
| 22 | 11835507260403376 |
| 23 | 57577781030368196 |