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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 20 |
| 5 | 0 |
| 6 | 1344 |
| 7 | 0 |
| 8 | 8160 |
| 9 | 0 |
| 10 | 349184 |
| 11 | 0 |
| 12 | 1397760 |
| 13 | 0 |
| 14 | 0 |
| 15 | 306774016 |
| 16 | 268431360 |
| 17 | 0 |
| 18 | 7635468288 |
| 19 | 0 |
| 20 | 494779760640 |
| 21 | 942438088704 |
| 22 | 0 |
| 23 | 0 |
| 24 | 105553109975040 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | 6004799480791040 |
| 29 | 0 |
| 30 | 192153583922184192 |
| 31 | 0 |
| 32 | 576460752169205760 |
| 33 | 0 |
| 34 | 49191317527028826112 |
| 35 | 0 |