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 | 28 |
| 7 | 81095 |
| 8 | 42752576 |
| 9 | 2436444603 |
| 10 | 53633024900 |
| 11 | 666519047964 |
| 12 | 5655962632720 |
| 13 | 36502953719310 |
| 14 | 191587564345044 |
| 15 | 854990702601025 |
| 16 | 3346890268570368 |
| 17 | 11756179090049177 |
| 18 | 37692541754516628 |
| 19 | 111774885566128630 |
| 20 | 309788198526691600 |