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 | 2 |
| 1 | 4 |
| 2 | 9 |
| 3 | 23 |
| 4 | 54 |
| 5 | 125 |
| 6 | 290 |
| 7 | 674 |
| 8 | 1567 |
| 9 | 3643 |
| 10 | 8469 |
| 11 | 19688 |
| 12 | 45769 |
| 13 | 106400 |
| 14 | 247350 |
| 15 | 575019 |
| 16 | 1336757 |
| 17 | 3107583 |
| 18 | 7224254 |
| 19 | 16794353 |
| 20 | 39042134 |
| 21 | 90761950 |
| 22 | 210995935 |
| 23 | 490506039 |
| 24 | 1140288197 |
| 25 | 2650848448 |
| 26 | 6162474989 |
| 27 | 14326016268 |
| 28 | 33303947274 |