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 | 55 |
| 3 | 935 |
| 4 | 21505 |
| 5 | 623645 |
| 6 | 21827575 |
| 7 | 894930575 |
| 8 | 42061737025 |
| 9 | 2229272062325 |
| 10 | 131527051677175 |
| 11 | 8549258359016375 |
| 12 | 606997343490162625 |
| 13 | 46738795448742522125 |
| 14 | 3879320022245629336375 |
| 15 | 345259481979861010937375 |
| 16 | 32799650788086796039050625 |
| 17 | 3312764729596766399944113125 |