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 | 1 |
| 7 | 9 |
| 8 | 134 |
| 9 | 1714 |
| 10 | 18436 |
| 11 | 167703 |
| 12 | 1327240 |
| 13 | 9372119 |
| 14 | 60324933 |
| 15 | 359730035 |
| 16 | 2012733260 |
| 17 | 10670975762 |
| 18 | 54028108819 |
| 19 | 262872075003 |
| 20 | 1235323112178 |
| 21 | 5630370812614 |