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 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 8 |
| 5 | 12 |
| 6 | 18 |
| 7 | 27 |
| 8 | 40 |
| 9 | 58 |
| 10 | 83 |
| 11 | 118 |
| 12 | 195 |
| 13 | 242 |
| 14 | -1387 |
| 15 | -338 |
| 16 | 75876 |
| 17 | 44491 |
| 18 | -3099115 |
| 19 | -2028539 |
| 20 | 129829195 |
| 21 | 91749709 |
| 22 | -5687984421 |
| 23 | -4236497556 |
| 24 | 263653557716 |
| 25 | 204087552038 |
| 26 | -12979768392096 |
| 27 | -10348229609729 |
| 28 | 679042377362009 |
| 29 | 554161706136054 |
| 30 | -37712174126966326 |