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 | 60 |
| 3 | 720 |
| 4 | 4080 |
| 5 | 15600 |
| 6 | 46620 |
| 7 | 117600 |
| 8 | 262080 |
| 9 | 531360 |
| 10 | 999900 |
| 11 | 1771440 |
| 12 | 2985840 |
| 13 | 4826640 |
| 14 | 7529340 |
| 15 | 11390400 |
| 16 | 16776960 |
| 17 | 24137280 |
| 18 | 34011900 |
| 19 | 47045520 |
| 20 | 63999600 |
| 21 | 85765680 |
| 22 | 113379420 |
| 23 | 148035360 |
| 24 | 191102400 |
| 25 | 244140000 |
| 26 | 308915100 |