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 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 476 |
| 9 | 20956 |
| 10 | 541960 |
| 11 | 10783530 |
| 12 | 183084580 |
| 13 | 2796467584 |
| 14 | 39641212284 |
| 15 | 532014841490 |
| 16 | 6852097042820 |
| 17 | 85509456576162 |
| 18 | 1041222110654522 |
| 19 | 12436416067831144 |
| 20 | 146290172122139436 |
| 21 | 1700035652369320714 |