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 | 2 |
| 2 | 3 |
| 3 | 4 |
| 4 | 6 |
| 5 | 8 |
| 6 | 18 |
| 7 | 40 |
| 8 | 230 |
| 9 | 4296 |
| 10 | 431206 |
| 11 | 162267272 |
| 12 | 201636689771 |
| 13 | 777816803942186 |
| 14 | 9865957936943931964 |
| 15 | 395886667549681689591841 |
| 16 | 53716176608076643470621234239 |
| 17 | 23524515269630339982914646821899537 |
| 18 | 35682168849414944013547274452501768506834 |