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 | 1 |
| 1 | -2 |
| 2 | 1 |
| 3 | -1 |
| 4 | 4 |
| 5 | -5 |
| 6 | 3 |
| 7 | -6 |
| 8 | 13 |
| 9 | -13 |
| 10 | 12 |
| 11 | -25 |
| 12 | 39 |
| 13 | -38 |
| 14 | 49 |
| 15 | -89 |
| 16 | 116 |
| 17 | -125 |
| 18 | 187 |
| 19 | -294 |
| 20 | 357 |
| 21 | -437 |
| 22 | 668 |
| 23 | -945 |
| 24 | 1151 |
| 25 | -1542 |
| 26 | 2281 |
| 27 | -3041 |
| 28 | 3844 |
| 29 | -5365 |
| 30 | 7603 |
| 31 | -9926 |
| 32 | 13053 |
| 33 | -18333 |
| 34 | 25132 |
| 35 | -32905 |
| 36 | 44439 |
| 37 | -61798 |
| 38 | 83169 |
| 39 | -110249 |
| 40 | 150676 |
| 41 | -206765 |
| 42 | 276587 |
| 43 | -371174 |
| 44 | 508117 |
| 45 | -690117 |
| 46 | 924348 |
| 47 | -1250465 |