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 | 1 |
| 4 | 4 |
| 5 | 8 |
| 6 | 50 |
| 7 | 54 |
| 8 | 284 |
| 9 | 525 |
| 10 | 2370 |
| 11 | 2872 |
| 12 | 22748 |
| 13 | 21866 |
| 14 | 131750 |
| 15 | 298792 |
| 16 | 904918 |
| 17 | 1341518 |
| 18 | 10745090 |
| 19 | 10748218 |
| 20 | 72889084 |
| 21 | 145274556 |
| 22 | 522819590 |
| 23 | 713023210 |
| 24 | 5892634240 |
| 25 | 7059926605 |
| 26 | 35300985550 |
| 27 | 70604008204 |