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 | 1 |
| 3 | 4 |
| 4 | 4 |
| 5 | 28 |
| 6 | 24 |
| 7 | 156 |
| 8 | 128 |
| 9 | 784 |
| 10 | 1120 |
| 11 | 5740 |
| 12 | 2880 |
| 13 | 33460 |
| 14 | 37128 |
| 15 | 150080 |
| 16 | 147456 |
| 17 | 1128256 |
| 18 | 931392 |
| 19 | 6446016 |
| 20 | 4677120 |
| 21 | 28514304 |
| 22 | 44450560 |
| 23 | 224075664 |
| 24 | 106168320 |
| 25 | 1265644800 |
| 26 | 1560708240 |
| 27 | 5970392064 |
| 28 | 5588803584 |
| 29 | 44560482148 |
| 30 | 33497856000 |
| 31 | 255263424000 |
| 32 | 196368924672 |
| 33 | 1210784762880 |