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 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 5 |
| 5 | 2 |
| 6 | 25 |
| 7 | 20 |
| 8 | 129 |
| 9 | 150 |
| 10 | 685 |
| 11 | 1008 |
| 12 | 3725 |
| 13 | 6410 |
| 14 | 20641 |
| 15 | 39500 |
| 16 | 116025 |
| 17 | 238782 |
| 18 | 659125 |
| 19 | 1425960 |
| 20 | 3773189 |
| 21 | 8448050 |
| 22 | 21717865 |
| 23 | 49786628 |
| 24 | 125485425 |
| 25 | 292368870 |
| 26 | 727000381 |
| 27 | 1712815200 |
| 28 | 4219739645 |
| 29 | 10018076762 |
| 30 | 24524328625 |
| 31 | 58529863100 |