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) |
|---|---|
| 5 | 13 |
| 6 | 73 |
| 7 | 505 |
| 8 | 4033 |
| 9 | 36289 |
| 10 | 362881 |
| 11 | 3991681 |
| 12 | 47900161 |
| 13 | 622702081 |
| 14 | 8717829121 |
| 15 | 130767436801 |
| 16 | 2092278988801 |
| 17 | 35568742809601 |
| 18 | 640237370572801 |
| 19 | 12164510040883201 |
| 20 | 243290200817664001 |
| 21 | 5109094217170944001 |