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 | 12 |
| 3 | 56 |
| 4 | 360 |
| 5 | 992 |
| 6 | 2016 |
| 7 | 16256 |
| 8 | 120960 |
| 9 | 131040 |
| 10 | 1571328 |
| 11 | 8714160 |
| 12 | 67100672 |
| 13 | 94279680 |
| 14 | 182131200 |
| 15 | 571963392 |
| 16 | 1379454720 |
| 17 | 4428914688 |
| 18 | 5517818880 |
| 19 | 17179738112 |
| 20 | 70912195200 |
| 21 | 153003540480 |
| 22 | 159991977600 |
| 23 | 175445913600 |
| 24 | 265734881280 |
| 25 | 274877382656 |
| 26 | 612014161920 |