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 | 18 |
| 3 | 323 |
| 4 | 5796 |
| 5 | 104005 |
| 6 | 1866294 |
| 7 | 33489287 |
| 8 | 600940872 |
| 9 | 10783446409 |
| 10 | 193501094490 |
| 11 | 3472236254411 |
| 12 | 62306751484908 |
| 13 | 1118049290473933 |
| 14 | 20062580477045886 |
| 15 | 360008399296352015 |
| 16 | 6460088606857290384 |
| 17 | 115921586524134874897 |
| 18 | 2080128468827570457762 |