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 | 0 |
| 3 | 0 |
| 4 | 200046 |
| 5 | 294912 |
| 6 | 23779584 |
| 7 | 82378752 |
| 8 | 1032132696 |
| 9 | 3570794496 |
| 10 | 21539288064 |
| 11 | 64122912768 |
| 12 | 266965225878 |
| 13 | 683889819648 |
| 14 | 2273486860032 |
| 15 | 5134106886144 |