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) |
|---|---|
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 16 |
| 7 | 63 |
| 8 | 328 |
| 9 | 1933 |
| 10 | 12633 |
| 11 | 87466 |
| 12 | 633015 |
| 13 | 4717745 |
| 14 | 35980100 |
| 15 | 279418926 |
| 16 | 2202903618 |
| 17 | 17590599410 |
| 18 | 142025760202 |
| 19 | 1157868883224 |
| 20 | 9520828261067 |
| 21 | 78888071847324 |
| 22 | 658158709983945 |
| 23 | 5525145717439001 |
| 24 | 46644670326913204 |
| 25 | 395812792437224022 |
| 26 | 3374572617006946447 |