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 | 2 |
| 3 | 1 |
| 4 | 7 |
| 5 | 0 |
| 6 | 23 |
| 7 | -9 |
| 8 | 78 |
| 9 | -59 |
| 10 | 275 |
| 11 | -296 |
| 12 | 1003 |
| 13 | -1341 |
| 14 | 3758 |
| 15 | -5775 |
| 16 | 14367 |
| 17 | -24176 |
| 18 | 55727 |
| 19 | -99521 |
| 20 | 218350 |
| 21 | -405459 |
| 22 | 861467 |
| 23 | -1641144 |
| 24 | 3414627 |
| 25 | -6615125 |
| 26 | 13576718 |
| 27 | -26592839 |
| 28 | 54092743 |
| 29 | -106717824 |
| 30 | 215810375 |
| 31 | -427778361 |
| 32 | 861773838 |
| 33 | -1713488171 |
| 34 | 3443252963 |