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 | -4 |
| 3 | 1 |
| 4 | 21 |
| 5 | -18 |
| 6 | 1 |
| 7 | -140 |
| 8 | 240 |
| 9 | -48 |
| 10 | 1 |
| 11 | 1140 |
| 12 | -3150 |
| 13 | 1300 |
| 14 | -100 |
| 15 | 1 |
| 16 | -11004 |
| 17 | 43620 |
| 18 | -29700 |
| 19 | 4800 |
| 20 | -180 |
| 21 | 1 |
| 22 | 123074 |
| 23 | -650769 |
| 24 | 647780 |
| 25 | -175175 |
| 26 | 13965 |
| 27 | -294 |
| 28 | 1 |
| 29 | -1566928 |
| 30 | 10517108 |
| 31 | -14190400 |
| 32 | 5676160 |
| 33 | -764400 |
| 34 | 34496 |
| 35 | -448 |
| 36 | 1 |
| 37 | 22390488 |
| 38 | -184052520 |
| 39 | 319680732 |
| 40 | -175091112 |
| 41 | 35160048 |
| 42 | -2698920 |
| 43 | 75600 |
| 44 | -648 |
| 45 | 1 |