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 | 1 |
| 1 | 28 |
| 2 | -274 |
| 3 | -66920 |
| 4 | -1004084 |
| 5 | 255091088 |
| 6 | 12454154824 |
| 7 | -1270601891552 |
| 8 | -127812323590000 |
| 9 | 7175629349576128 |
| 10 | 1417946567012111584 |
| 11 | -36215654642176309888 |
| 12 | -17516100476867891291456 |
| 13 | -30656862015230525822720 |
| 14 | 240058053822414522099649664 |
| 15 | 7175714947197201167276319232 |