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 | -6 |
| 2 | -20 |
| 3 | -76 |
| 4 | -272 |
| 5 | -580 |
| 6 | 3760 |
| 7 | 77324 |
| 8 | 896848 |
| 9 | 8869820 |
| 10 | 81550960 |
| 11 | 719926124 |
| 12 | 6196609168 |
| 13 | 52439953820 |
| 14 | 438516694960 |
| 15 | 3635082523724 |
| 16 | 29935019892688 |
| 17 | 245264010263420 |
| 18 | 2001462391659760 |
| 19 | 16280541150478124 |
| 20 | 132087583623451408 |