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 | 2 |
| 2 | 4 |
| 3 | 14 |
| 4 | 36 |
| 5 | 99 |
| 6 | 274 |
| 7 | 813 |
| 8 | 2278 |
| 9 | 6692 |
| 10 | 19206 |
| 11 | 56687 |
| 12 | 164416 |
| 13 | 486052 |
| 14 | 1422654 |
| 15 | 4214023 |
| 16 | 12408476 |
| 17 | 36825663 |
| 18 | 108926976 |
| 19 | 323856358 |
| 20 | 961177042 |
| 21 | 2862551860 |
| 22 | 8518115200 |
| 23 | 25407468667 |
| 24 | 75763113682 |
| 25 | 226297498429 |
| 26 | 675951314988 |
| 27 | 2021528322571 |
| 28 | 6046881759308 |
| 29 | 18104307275968 |
| 30 | 54219605813884 |