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 | 4 |
| 7 | 13 |
| 8 | 44 |
| 9 | 149 |
| 10 | 504 |
| 11 | 1701 |
| 12 | 5715 |
| 13 | 19079 |
| 14 | 63218 |
| 15 | 207803 |
| 16 | 677598 |
| 17 | 2192383 |
| 18 | 7041688 |
| 19 | 22463815 |
| 20 | 71216406 |
| 21 | 224495351 |
| 22 | 704036264 |
| 23 | 2197641219 |
| 24 | 6831066997 |
| 25 | 21152812449 |
| 26 | 65276358340 |
| 27 | 200814955029 |
| 28 | 616052453764 |
| 29 | 1885109044861 |