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 | 16 |
| 3 | 308 |
| 4 | 11048 |
| 5 | 639972 |
| 6 | 54671188 |
| 7 | 6471586298 |
| 8 | 1014487323984 |
| 9 | 203492881479464 |
| 10 | 50842872702666524 |
| 11 | 15484223252089602342 |
| 12 | 5646860009850046968472 |
| 13 | 2429577079632942917710580 |