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 | 6 |
| 2 | 41 |
| 3 | 316 |
| 4 | 2337 |
| 5 | 16682 |
| 6 | 117433 |
| 7 | 823200 |
| 8 | 5764289 |
| 9 | 40352878 |
| 10 | 282474249 |
| 11 | 1977325412 |
| 12 | 13841285473 |
| 13 | 96889008210 |
| 14 | 678223070105 |
| 15 | 4747561506568 |
| 16 | 33232930565505 |
| 17 | 232630513982294 |
| 18 | 1628413597904617 |
| 19 | 11398895185366284 |
| 20 | 79792266297604001 |
| 21 | 558545864083274746 |