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 | 1 |
| 2 | 1 |
| 3 | -1 |
| 4 | -53 |
| 5 | -1083 |
| 6 | -24099 |
| 7 | -120477 |
| 8 | 115958039 |
| 9 | 30323462809 |
| 10 | 7554183583865 |
| 11 | 2000735772375143 |
| 12 | 483441809221224835 |
| 13 | -15004002104132799283 |
| 14 | -243176330287496140346187 |
| 15 | -424738050855195910944014901 |
| 16 | -660294012298780945217254277745 |