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 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 125 |
| 5 | 722 |
| 6 | 2565 |
| 7 | 7180 |
| 8 | 17335 |
| 9 | 37750 |
| 10 | 76093 |
| 11 | 144340 |
| 12 | 260590 |
| 13 | 451440 |
| 14 | 755040 |
| 15 | 1224964 |
| 16 | 1935050 |
| 17 | 2985380 |
| 18 | 4509590 |
| 19 | 6683720 |
| 20 | 9736835 |
| 21 | 13963670 |
| 22 | 19739575 |
| 23 | 27538060 |
| 24 | 37951265 |
| 25 | 51713706 |
| 26 | 69729675 |
| 27 | 93104700 |
| 28 | 123181500 |