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 | 3 |
| 2 | 29 |
| 3 | 237 |
| 4 | 1841 |
| 5 | 13893 |
| 6 | 102689 |
| 7 | 747477 |
| 8 | 5380481 |
| 9 | 38419653 |
| 10 | 272767649 |
| 11 | 1928673717 |
| 12 | 13597673921 |
| 13 | 95669893413 |
| 14 | 672124323809 |
| 15 | 4717058247957 |
| 16 | 33080385660161 |
| 17 | 231867703543173 |
| 18 | 1624599287803169 |
| 19 | 11379822860782197 |
| 20 | 79696902351707201 |
| 21 | 558069037383336933 |
| 22 | 3907436894168837729 |