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 | 13 |
| 7 | 105 |
| 8 | 680 |
| 9 | 3876 |
| 10 | 20349 |
| 11 | 100947 |
| 12 | 480700 |
| 13 | 2220075 |
| 14 | 10015005 |
| 15 | 44352165 |
| 16 | 193536720 |
| 17 | 834451800 |
| 18 | 3562467300 |
| 19 | 15084504396 |
| 20 | 63432274896 |
| 21 | 265182149218 |
| 22 | 1103068603890 |
| 23 | 4568648125690 |
| 24 | 18851684897584 |