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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 32 |
| 6 | 218 |
| 7 | 2060 |
| 8 | 23054 |
| 9 | 314242 |
| 10 | 4897410 |
| 11 | 87427276 |
| 12 | 1741312444 |
| 13 | 38482278928 |
| 14 | 931618115860 |
| 15 | 24554678866736 |
| 16 | 699328394272236 |
| 17 | 21410158708401980 |
| 18 | 701011980397033052 |
| 19 | 24445424273647475096 |
| 20 | 904440666571331841992 |
| 21 | 35386719095200164370912 |
| 22 | 1459756349974815778252152 |