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 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 5 |
| 4 | 5 |
| 5 | 0 |
| 6 | -14 |
| 7 | -41 |
| 8 | -81 |
| 9 | -121 |
| 10 | -121 |
| 11 | 0 |
| 12 | 364 |
| 13 | 1093 |
| 14 | 2187 |
| 15 | 3281 |
| 16 | 3281 |
| 17 | 0 |
| 18 | -9842 |
| 19 | -29525 |
| 20 | -59049 |
| 21 | -88573 |
| 22 | -88573 |
| 23 | 0 |
| 24 | 265720 |
| 25 | 797161 |
| 26 | 1594323 |
| 27 | 2391485 |
| 28 | 2391485 |
| 29 | 0 |
| 30 | -7174454 |
| 31 | -21523361 |
| 32 | -43046721 |
| 33 | -64570081 |
| 34 | -64570081 |
| 35 | 0 |
| 36 | 193710244 |
| 37 | 581130733 |
| 38 | 1162261467 |