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 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 92 |
| 4 | 1304 |
| 5 | 20198 |
| 6 | 332520 |
| 7 | 5703724 |
| 8 | 100847976 |
| 9 | 1824927697 |
| 10 | 33634879304 |
| 11 | 629201396744 |
| 12 | 11915930584384 |
| 13 | 228010216559592 |
| 14 | 4401559021963488 |
| 15 | 85616787777724400 |
| 16 | 1676436841812675760 |
| 17 | 33017479163392717192 |
| 18 | 653643628799220208104 |
| 19 | 12999812350464606307796 |