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 | 117 |
| 2 | 3780 |
| 3 | 66960 |
| 4 | 167400 |
| 5 | 406224 |
| 6 | 1097280 |
| 7 | 6656832 |
| 8 | 13035330 |
| 9 | 29410290 |
| 10 | 4529295360 |
| 11 | 27477725184 |
| 12 | 88071903612 |
| 13 | 1159632322560 |
| 14 | 7035102756864 |
| 15 | 18554223329280 |
| 16 | 22385029489560 |
| 17 | 54934276752360 |
| 18 | 112562288197632 |
| 19 | 125356165141536 |
| 20 | 307631949813216 |
| 21 | 1317932346931200 |