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 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 19 |
| 4 | 217 |
| 5 | 3961 |
| 6 | 105963 |
| 7 | 3908059 |
| 8 | 190065457 |
| 9 | 11785687921 |
| 10 | 907546301523 |
| 11 | 84965187064099 |
| 12 | 9504085749177097 |
| 13 | 1251854782837499881 |
| 14 | 191781185418766714683 |
| 15 | 33810804270120276636139 |
| 16 | 6796689405759438360407137 |
| 17 | 1545327493049348356667631841 |