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 | 3 |
| 2 | 2 |
| 3 | 1 |
| 4 | 91 |
| 5 | 6 |
| 6 | 5 |
| 7 | 1 |
| 8 | 5 |
| 9 | 1 |
| 10 | 8041 |
| 11 | 15870 |
| 12 | 39865 |
| 13 | 1 |
| 14 | 251625 |
| 15 | 637064 |
| 16 | 1829661 |
| 17 | 4124240 |
| 18 | 10553093 |
| 19 | 1 |
| 20 | 69709253 |
| 21 | 179992156 |
| 22 | 465769749 |
| 23 | 1210576800 |
| 24 | 3140421235 |
| 25 | 13974959892 |