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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 7 |
| 5 | 22 |
| 6 | 58 |
| 7 | 138 |
| 8 | 319 |
| 9 | 750 |
| 10 | 1810 |
| 11 | 4427 |
| 12 | 10828 |
| 13 | 26349 |
| 14 | 63862 |
| 15 | 154603 |
| 16 | 374521 |
| 17 | 908140 |
| 18 | 2203162 |
| 19 | 5344988 |
| 20 | 12964858 |
| 21 | 31443013 |
| 22 | 76253683 |
| 23 | 184929945 |
| 24 | 448506736 |
| 25 | 1087774536 |
| 26 | 2638209313 |
| 27 | 6398479259 |
| 28 | 15518219326 |
| 29 | 37636240539 |
| 30 | 91279009255 |
| 31 | 221378866489 |