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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 15 |
| 6 | 27 |
| 7 | 89 |
| 8 | 165 |
| 9 | 585 |
| 10 | 1113 |
| 11 | 4097 |
| 12 | 7917 |
| 13 | 29927 |
| 14 | 58499 |
| 15 | 225585 |
| 16 | 444793 |
| 17 | 1741521 |
| 18 | 3457027 |
| 19 | 13699699 |
| 20 | 27342421 |
| 21 | 109420549 |
| 22 | 219358315 |
| 23 | 884987529 |
| 24 | 1780751883 |
| 25 | 7233519619 |
| 26 | 14600965705 |
| 27 | 59656252987 |
| 28 | 120742510607 |
| 29 | 495811828759 |
| 30 | 1005862035461 |