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 | 12 |
| 2 | 144 |
| 3 | 396 |
| 4 | 2460 |
| 5 | 9216 |
| 6 | 46956 |
| 7 | 196812 |
| 8 | 932688 |
| 9 | 4086060 |
| 10 | 18819228 |
| 11 | 83939328 |
| 12 | 382160076 |
| 13 | 1717133964 |
| 14 | 7780911120 |
| 15 | 35067371724 |
| 16 | 158593617564 |
| 17 | 715647771648 |
| 18 | 3233959733292 |
| 19 | 14600607874380 |
| 20 | 65957362026192 |
| 21 | 297845692391532 |