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 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 32 |
| 5 | 320 |
| 6 | 6144 |
| 7 | 229376 |
| 8 | 16777216 |
| 9 | 2415919104 |
| 10 | 687194767360 |
| 11 | 387028092977152 |
| 12 | 432345564227567616 |
| 13 | 959230691832896684032 |
| 14 | 4231240368651202111471616 |
| 15 | 37138201178561408246973726720 |
| 16 | 649037107316853453566312041152512 |
| 17 | 22596875928343569839364720024765857792 |