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 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 9 |
| 7 | 20 |
| 8 | 44 |
| 9 | 101 |
| 10 | 239 |
| 11 | 584 |
| 12 | 1468 |
| 13 | 3789 |
| 14 | 10027 |
| 15 | 27161 |
| 16 | 75211 |
| 17 | 212651 |
| 18 | 613228 |
| 19 | 1801879 |
| 20 | 5390071 |
| 21 | 16401436 |
| 22 | 50730640 |
| 23 | 159393146 |
| 24 | 508408373 |
| 25 | 1645330314 |
| 26 | 5399614435 |
| 27 | 17960973056 |
| 28 | 60528130675 |