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 | 1 |
| 1 | 5 |
| 2 | 20 |
| 3 | 80 |
| 4 | 320 |
| 5 | 1280 |
| 6 | 5120 |
| 7 | 20480 |
| 8 | 81920 |
| 9 | 327680 |
| 10 | 1310720 |
| 11 | 5242880 |
| 12 | 20971520 |
| 13 | 83886080 |
| 14 | 335544320 |
| 15 | 1342177280 |