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) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 126 |
| 3 | 2184 |
| 4 | 16380 |
| 5 | 78120 |
| 6 | 279930 |
| 7 | 823536 |
| 8 | 2097144 |
| 9 | 4782960 |
| 10 | 9999990 |
| 11 | 19487160 |
| 12 | 35831796 |
| 13 | 62748504 |
| 14 | 105413490 |
| 15 | 170859360 |
| 16 | 268435440 |
| 17 | 410338656 |
| 18 | 612220014 |
| 19 | 893871720 |
| 20 | 1279999980 |
| 21 | 1801088520 |
| 22 | 2494357866 |
| 23 | 3404825424 |
| 24 | 4586471400 |
| 25 | 6103515600 |
| 26 | 8031810150 |