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 | 0 |
| 4 | -1 |
| 5 | 2 |
| 6 | 15 |
| 7 | 27 |
| 8 | -1 |
| 9 | -76 |
| 10 | 19 |
| 11 | 719 |
| 12 | 1687 |
| 13 | 184 |
| 14 | -5976 |
| 15 | -3749 |
| 16 | 44093 |
| 17 | 130933 |
| 18 | 42026 |
| 19 | -512833 |
| 20 | -667101 |
| 21 | 2976177 |
| 22 | 11391169 |
| 23 | 6608432 |
| 24 | -45604863 |
| 25 | -87819235 |
| 26 | 202544340 |
| 27 | 1053407806 |
| 28 | 922859161 |
| 29 | -4085924365 |
| 30 | -10600384406 |
| 31 | 12656739909 |
| 32 | 100646660458 |
| 33 | 121472828448 |
| 34 | -360976456530 |