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 | 22 |
| 3 | 247 |
| 4 | 2569 |
| 5 | 25556 |
| 6 | 250853 |
| 7 | 2444359 |
| 8 | 23727305 |
| 9 | 229924367 |
| 10 | 2227121996 |
| 11 | 21578747909 |
| 12 | 209214982913 |
| 13 | 2030133769624 |
| 14 | 19717814526785 |
| 15 | 191693417109381 |
| 16 | 1865380637252270 |
| 17 | 18168907486812690 |
| 18 | 177123437184971927 |
| 19 | 1728190923820610000 |