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 | 3 |
| 2 | 7 |
| 3 | 16 |
| 4 | 36 |
| 5 | 80 |
| 6 | 177 |
| 7 | 391 |
| 8 | 863 |
| 9 | 1904 |
| 10 | 4200 |
| 11 | 9264 |
| 12 | 20433 |
| 13 | 45067 |
| 14 | 99399 |
| 15 | 219232 |
| 16 | 483532 |
| 17 | 1066464 |
| 18 | 2352161 |
| 19 | 5187855 |
| 20 | 11442175 |
| 21 | 25236512 |
| 22 | 55660880 |
| 23 | 122763936 |
| 24 | 270764385 |
| 25 | 597189651 |
| 26 | 1317143239 |
| 27 | 2905050864 |
| 28 | 6407291380 |
| 29 | 14131726000 |
| 30 | 31168502865 |
| 31 | 68744297111 |