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 | 4 |
| 4 | 25 |
| 5 | 176 |
| 6 | 1353 |
| 7 | 11012 |
| 8 | 93329 |
| 9 | 815104 |
| 10 | 7285489 |
| 11 | 66324644 |
| 12 | 612863337 |
| 13 | 5733381616 |
| 14 | 54195878137 |
| 15 | 516852285668 |
| 16 | 4966883732129 |
| 17 | 48049936644736 |
| 18 | 467566946973537 |
| 19 | 4573486005681092 |
| 20 | 44942852084894777 |
| 21 | 443484037981300144 |
| 22 | 4392621673072766505 |