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 | 5 |
| 2 | 28 |
| 3 | 220 |
| 4 | 2380 |
| 5 | 33649 |
| 6 | 593775 |
| 7 | 12620256 |
| 8 | 314457495 |
| 9 | 8996462475 |
| 10 | 290752384208 |
| 11 | 10477677064400 |
| 12 | 416579843773639 |
| 13 | 18114175790089400 |
| 14 | 855130180330364620 |
| 15 | 43553532185070076800 |
| 16 | 2380434572658017204175 |