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 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 48 |
| 6 | 96 |
| 7 | 288 |
| 8 | 576 |
| 9 | 2880 |
| 10 | 5760 |
| 11 | 17280 |
| 12 | 34560 |
| 13 | 138240 |
| 14 | 276480 |
| 15 | 829440 |
| 16 | 1658880 |
| 17 | 9953280 |
| 18 | 19906560 |
| 19 | 59719680 |
| 20 | 119439360 |
| 21 | 477757440 |
| 22 | 955514880 |
| 23 | 2866544640 |
| 24 | 5733089280 |
| 25 | 28665446400 |
| 26 | 57330892800 |
| 27 | 171992678400 |
| 28 | 343985356800 |
| 29 | 1375941427200 |
| 30 | 2751882854400 |