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 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 4 |
| 8 | 114 |
| 9 | 1384 |
| 10 | 9890 |
| 11 | 50662 |
| 12 | 205512 |
| 13 | 698688 |
| 14 | 2074530 |
| 15 | 5525902 |
| 16 | 13476246 |
| 17 | 30522678 |
| 18 | 64968996 |
| 19 | 131070600 |
| 20 | 252492296 |
| 21 | 467017054 |
| 22 | 833501728 |
| 23 | 1440839952 |
| 24 | 2420878990 |
| 25 | 3964168632 |
| 26 | 6342428908 |
| 27 | 9934738024 |
| 28 | 15264432954 |