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 | -3 |
| 4 | 3 |
| 5 | -4 |
| 6 | 6 |
| 7 | -7 |
| 8 | 10 |
| 9 | -13 |
| 10 | 17 |
| 11 | -23 |
| 12 | 30 |
| 13 | -40 |
| 14 | 53 |
| 15 | -70 |
| 16 | 93 |
| 17 | -123 |
| 18 | 163 |
| 19 | -216 |
| 20 | 286 |
| 21 | -379 |
| 22 | 502 |
| 23 | -665 |
| 24 | 881 |
| 25 | -1167 |
| 26 | 1546 |
| 27 | -2048 |
| 28 | 2713 |
| 29 | -3594 |
| 30 | 4761 |
| 31 | -6307 |
| 32 | 8355 |
| 33 | -11068 |
| 34 | 14662 |
| 35 | -19423 |
| 36 | 25730 |
| 37 | -34085 |
| 38 | 45153 |
| 39 | -59815 |
| 40 | 79238 |