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 | 1 |
| 3 | -1 |
| 4 | 2 |
| 5 | -3 |
| 6 | 3 |
| 7 | -4 |
| 8 | 6 |
| 9 | -7 |
| 10 | 8 |
| 11 | -10 |
| 12 | 13 |
| 13 | -16 |
| 14 | 18 |
| 15 | -22 |
| 16 | 28 |
| 17 | -33 |
| 18 | 38 |
| 19 | -45 |
| 20 | 55 |
| 21 | -65 |
| 22 | 74 |
| 23 | -87 |
| 24 | 104 |
| 25 | -121 |
| 26 | 138 |
| 27 | -160 |
| 28 | 188 |
| 29 | -217 |
| 30 | 247 |
| 31 | -284 |
| 32 | 330 |
| 33 | -378 |
| 34 | 428 |
| 35 | -489 |
| 36 | 562 |
| 37 | -640 |
| 38 | 722 |
| 39 | -820 |
| 40 | 936 |
| 41 | -1059 |
| 42 | 1191 |
| 43 | -1345 |
| 44 | 1524 |
| 45 | -1717 |
| 46 | 1924 |
| 47 | -2163 |
| 48 | 2438 |
| 49 | -2734 |
| 50 | 3054 |
| 51 | -3419 |