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 | 12 |
| 3 | 48 |
| 4 | 152 |
| 5 | 424 |
| 6 | 1096 |
| 7 | 2696 |
| 8 | 6408 |
| 9 | 14856 |
| 10 | 33800 |
| 11 | 75784 |
| 12 | 167944 |
| 13 | 368648 |
| 14 | 802824 |
| 15 | 1736712 |
| 16 | 3735560 |
| 17 | 7995400 |
| 18 | 17039368 |
| 19 | 36175880 |
| 20 | 76546056 |
| 21 | 161480712 |
| 22 | 339738632 |
| 23 | 713031688 |
| 24 | 1493172232 |
| 25 | 3120562184 |
| 26 | 6509559816 |
| 27 | 13555990536 |
| 28 | 28185722888 |
| 29 | 58518929416 |