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 | 2 |
| 2 | 15 |
| 3 | 417 |
| 4 | 42176 |
| 5 | 15701273 |
| 6 | 21418970801 |
| 7 | 107224417436160 |
| 8 | 1968910887183791359 |
| 9 | 132633131268024896655873 |
| 10 | 32775983842712963307230834176 |
| 11 | 29712661745725058784174163778464369 |