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 | 2 |
| 2 | 12 |
| 3 | 24 |
| 4 | 144 |
| 5 | 288 |
| 6 | 1728 |
| 7 | 3456 |
| 8 | 20736 |
| 9 | 41472 |
| 10 | 248832 |
| 11 | 497664 |
| 12 | 2985984 |
| 13 | 5971968 |
| 14 | 35831808 |
| 15 | 71663616 |
| 16 | 429981696 |
| 17 | 859963392 |
| 18 | 5159780352 |
| 19 | 10319560704 |
| 20 | 61917364224 |
| 21 | 123834728448 |
| 22 | 743008370688 |
| 23 | 1486016741376 |
| 24 | 8916100448256 |
| 25 | 17832200896512 |
| 26 | 106993205379072 |
| 27 | 213986410758144 |