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 | 3 |
| 2 | 1 |
| 3 | 6 |
| 4 | 19 |
| 5 | 63 |
| 6 | 208 |
| 7 | 687 |
| 8 | 2269 |
| 9 | 7494 |
| 10 | 24751 |
| 11 | 81747 |
| 12 | 269992 |
| 13 | 891723 |
| 14 | 2945161 |
| 15 | 9727206 |
| 16 | 32126779 |
| 17 | 106107543 |
| 18 | 350449408 |
| 19 | 1157455767 |
| 20 | 3822816709 |
| 21 | 12625905894 |
| 22 | 41700534391 |
| 23 | 137727509067 |
| 24 | 454883061592 |
| 25 | 1502376693843 |
| 26 | 4962013143121 |
| 27 | 16388416123206 |
| 28 | 54127261512739 |