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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 2 |
| 6 | 9 |
| 7 | 47 |
| 8 | 420 |
| 9 | 4673 |
| 10 | 63253 |
| 11 | 927238 |
| 12 | 14342093 |
| 13 | 229607392 |
| 14 | 3776227106 |
| 15 | 63482545872 |
| 16 | 1087322656758 |
| 17 | 18927037827561 |