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 | 20 |
| 5 | 12 |
| 6 | 1 |
| 7 | 120 |
| 8 | 128 |
| 9 | 24 |
| 10 | 1 |
| 11 | 840 |
| 12 | 1400 |
| 13 | 440 |
| 14 | 40 |
| 15 | 1 |
| 16 | 6720 |
| 17 | 16240 |
| 18 | 7560 |
| 19 | 1120 |
| 20 | 60 |
| 21 | 1 |
| 22 | 60480 |
| 23 | 201600 |
| 24 | 129640 |
| 25 | 27720 |
| 26 | 2380 |
| 27 | 84 |
| 28 | 1 |
| 29 | 604800 |
| 30 | 2681280 |
| 31 | 2275840 |
| 32 | 656320 |
| 33 | 80080 |
| 34 | 4480 |
| 35 | 112 |
| 36 | 1 |
| 37 | 6652800 |
| 38 | 38142720 |
| 39 | 41370560 |
| 40 | 15402240 |
| 41 | 2498160 |
| 42 | 196560 |