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 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 12 |
| 5 | 31 |
| 6 | 83 |
| 7 | 233 |
| 8 | 661 |
| 9 | 1893 |
| 10 | 5445 |
| 11 | 15720 |
| 12 | 45510 |
| 13 | 132069 |
| 14 | 384049 |
| 15 | 1118822 |
| 16 | 3264644 |
| 17 | 9539789 |
| 18 | 27913085 |
| 19 | 81769238 |
| 20 | 239794424 |
| 21 | 703906721 |
| 22 | 2068153901 |
| 23 | 6081507833 |
| 24 | 17896695833 |
| 25 | 52703944967 |
| 26 | 155310270103 |
| 27 | 457956633828 |
| 28 | 1351132539606 |
| 29 | 3988457429607 |