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) |
|---|---|
| 4 | 1 |
| 5 | 12 |
| 6 | 343 |
| 7 | 3864 |
| 8 | 26990 |
| 9 | 140455 |
| 10 | 599801 |
| 11 | 2228414 |
| 12 | 7486615 |
| 13 | 23370193 |
| 14 | 69141497 |
| 15 | 196766283 |
| 16 | 544680787 |
| 17 | 1478898009 |
| 18 | 3962865228 |
| 19 | 10526310127 |
| 20 | 27802386717 |
| 21 | 73170829088 |
| 22 | 192150938490 |
| 23 | 503938185601 |
| 24 | 1320621962194 |
| 25 | 3459303317894 |
| 26 | 9059231670566 |
| 27 | 23721098636714 |