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 | 8 |
| 2 | 21 |
| 3 | 168 |
| 4 | 780 |
| 5 | 4599 |
| 6 | 24246 |
| 7 | 134440 |
| 8 | 728537 |
| 9 | 3988862 |
| 10 | 21739002 |
| 11 | 118720559 |
| 12 | 647758554 |
| 13 | 3535719686 |
| 14 | 19295840383 |
| 15 | 105313615878 |
| 16 | 574764393110 |
| 17 | 3136909949941 |
| 18 | 17120293581344 |
| 19 | 93437607513222 |
| 20 | 509954720089427 |