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 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 3 |
| 4 | 33 |
| 5 | 33 |
| 6 | 429 |
| 7 | 429 |
| 8 | 429 |
| 9 | 858 |
| 10 | 4862 |
| 11 | 14586 |
| 12 | 25194 |
| 13 | 25194 |
| 14 | 1938 |
| 15 | 21318 |
| 16 | 490314 |
| 17 | 245157 |
| 18 | 72105 |
| 19 | 312455 |
| 20 | 148005 |
| 21 | 148005 |
| 22 | 4292145 |
| 23 | 390195 |
| 24 | 525915 |
| 25 | 2103660 |
| 26 | 4628052 |
| 27 | 6052068 |
| 28 | 672452 |
| 29 | 2017356 |
| 30 | 2573868 |