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 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 12 |
| 6 | 34 |
| 7 | 108 |
| 8 | 344 |
| 9 | 1136 |
| 10 | 3796 |
| 11 | 12920 |
| 12 | 44442 |
| 13 | 154596 |
| 14 | 542336 |
| 15 | 1917648 |
| 16 | 6825464 |
| 17 | 24439008 |
| 18 | 87962312 |
| 19 | 318087216 |
| 20 | 1155090092 |
| 21 | 4210494616 |
| 22 | 15400782912 |
| 23 | 56508464736 |
| 24 | 207935588586 |
| 25 | 767162495940 |
| 26 | 2837260332472 |
| 27 | 10516827106016 |
| 28 | 39063666532784 |
| 29 | 145378611426512 |