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 | 4 |
| 2 | 32 |
| 3 | 219 |
| 4 | 1575 |
| 5 | 11283 |
| 6 | 80972 |
| 7 | 581057 |
| 8 | 4169867 |
| 9 | 29924442 |
| 10 | 214748731 |
| 11 | 1541115372 |
| 12 | 11059607816 |
| 13 | 79367792570 |
| 14 | 569572322542 |
| 15 | 4087459410676 |
| 16 | 29333104460805 |
| 17 | 210505091515979 |
| 18 | 1510661567154766 |
| 19 | 10841060204501930 |
| 20 | 77799415112548482 |