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) |
|---|---|
| 1 | 0 |
| 2 | 20412 |
| 3 | 1365336 |
| 4 | 74853576 |
| 5 | 3719884392 |
| 6 | 174924572760 |
| 7 | 7934992835112 |
| 8 | 350946381867480 |
| 9 | 15232155757251048 |
| 10 | 651580499598523992 |
| 11 | 27551808205246504872 |
| 12 | 1154085846201751972824 |
| 13 | 47965168186749101620584 |