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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 105 |
| 6 | 2625 |
| 7 | 42075 |
| 8 | 554820 |
| 9 | 6578550 |
| 10 | 73169250 |
| 11 | 781319370 |
| 12 | 8122058850 |
| 13 | 82922497890 |
| 14 | 836339477160 |
| 15 | 8366154130425 |
| 16 | 83235403604220 |
| 17 | 825247074255735 |
| 18 | 8165187992777430 |
| 19 | 80704316324506860 |
| 20 | 797435573602269015 |
| 21 | 7881226621071221625 |
| 22 | 77939438593071188565 |