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 | 2 |
| 1 | 1 |
| 2 | -1 |
| 3 | -1 |
| 4 | 5 |
| 5 | 1 |
| 6 | -521 |
| 7 | -29 |
| 8 | 1067 |
| 9 | 13221 |
| 10 | -538019 |
| 11 | -692393 |
| 12 | 2088537 |
| 13 | 3155999 |
| 14 | -27611845 |
| 15 | -33200670659 |
| 16 | 1202005038007 |
| 17 | 40366435189 |
| 18 | -29289910899229 |
| 19 | -14754517273097 |
| 20 | 1825124640773023 |
| 21 | 18449097055233961 |
| 22 | -250479143430425927 |
| 23 | -1976767636081931863 |
| 24 | 1419438523008706978221 |