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 | 64 |
| 3 | 576 |
| 4 | 4672 |
| 5 | 37440 |
| 6 | 299584 |
| 7 | 2396736 |
| 8 | 19173952 |
| 9 | 153391680 |
| 10 | 1227133504 |
| 11 | 9817068096 |
| 12 | 78536544832 |
| 13 | 628292358720 |
| 14 | 5026338869824 |
| 15 | 40210710958656 |
| 16 | 321685687669312 |
| 17 | 2573485501354560 |
| 18 | 20587884010836544 |
| 19 | 164703072086692416 |
| 20 | 1317624576693539392 |