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 | 20 |
| 2 | 475 |
| 3 | 9996 |
| 4 | 186732 |
| 5 | 3283890 |
| 6 | 55491832 |
| 7 | 911930096 |
| 8 | 14681855846 |
| 9 | 232688402028 |
| 10 | 3642322709900 |
| 11 | 56444213311842 |
| 12 | 867475989937560 |
| 13 | 13239446101273360 |
| 14 | 200865483664370358 |
| 15 | 3031934392327858732 |
| 16 | 45561723449682618252 |