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 | 6 |
| 3 | 46 |
| 4 | 406 |
| 5 | 3901 |
| 6 | 39627 |
| 7 | 418592 |
| 8 | 4551672 |
| 9 | 50610692 |
| 10 | 572807157 |
| 11 | 6577068383 |
| 12 | 76426719408 |
| 13 | 897078662538 |
| 14 | 10620634999318 |
| 15 | 126676885170703 |
| 16 | 1520759193166329 |
| 17 | 18361269213121164 |
| 18 | 222814883564042704 |
| 19 | 2716125963857227904 |
| 20 | 33244557641365865109 |