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) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 6 |
| 4 | 15 |
| 5 | 66 |
| 6 | 210 |
| 7 | 715 |
| 8 | 7315 |
| 9 | 38571 |
| 10 | 254541 |
| 11 | 728365 |
| 12 | 11243155 |
| 13 | 58524466 |
| 14 | 812646121 |
| 15 | 5163068911 |
| 16 | 58720148851 |
| 17 | 555409903686 |
| 18 | 4339149420606 |
| 19 | 69322940121436 |
| 20 | 490005293940085 |
| 21 | 5819629108725510 |
| 22 | 76622240600506315 |