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) |
|---|---|
| 5 | 1 |
| 6 | 3 |
| 7 | 24 |
| 8 | 150 |
| 9 | 825 |
| 10 | 4205 |
| 11 | 20384 |
| 12 | 95472 |
| 13 | 436050 |
| 14 | 1954150 |
| 15 | 8629528 |
| 16 | 37665030 |
| 17 | 162845865 |
| 18 | 698599125 |
| 19 | 2977488000 |
| 20 | 12620579140 |
| 21 | 53243068230 |
| 22 | 223707978090 |
| 23 | 936619554000 |
| 24 | 3909283969500 |
| 25 | 16272003594658 |
| 26 | 67565854800378 |
| 27 | 279942274434624 |