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 | -2 |
| 2 | 3 |
| 3 | -5 |
| 4 | 7 |
| 5 | -11 |
| 6 | 16 |
| 7 | -24 |
| 8 | 36 |
| 9 | -54 |
| 10 | 81 |
| 11 | -122 |
| 12 | 183 |
| 13 | -275 |
| 14 | 412 |
| 15 | -618 |
| 16 | 927 |
| 17 | -1391 |
| 18 | 2086 |
| 19 | -3129 |
| 20 | 4693 |
| 21 | -7040 |
| 22 | 10560 |
| 23 | -15840 |
| 24 | 23760 |
| 25 | -35640 |
| 26 | 53460 |
| 27 | -80190 |
| 28 | 120285 |
| 29 | -180428 |
| 30 | 270642 |
| 31 | -405963 |
| 32 | 608944 |
| 33 | -913416 |
| 34 | 1370124 |
| 35 | -2055186 |
| 36 | 3082779 |
| 37 | -4624169 |
| 38 | 6936253 |
| 39 | -10404380 |
| 40 | 15606570 |
| 41 | -23409855 |
| 42 | 35114782 |