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 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 4 |
| 6 | -4 |
| 7 | 3 |
| 8 | -2 |
| 9 | 1 |
| 10 | -24 |
| 11 | 36 |
| 12 | -27 |
| 13 | 13 |
| 14 | -6 |
| 15 | 3 |
| 16 | -1 |
| 17 | 182 |
| 18 | -354 |
| 19 | 330 |
| 20 | -198 |
| 21 | 85 |
| 22 | -28 |
| 23 | 10 |
| 24 | -4 |
| 25 | 1 |
| 26 | -1730 |
| 27 | 4090 |
| 28 | -4480 |
| 29 | 3120 |
| 30 | -1595 |
| 31 | 631 |
| 32 | -195 |
| 33 | 50 |
| 34 | -15 |
| 35 | 5 |
| 36 | -1 |
| 37 | 19802 |
| 38 | -55270 |
| 39 | 70430 |
| 40 | -55730 |
| 41 | 31630 |
| 42 | -14018 |
| 43 | 5101 |
| 44 | -1536 |
| 45 | 375 |
| 46 | -80 |
| 47 | 21 |
| 48 | -6 |
| 49 | 1 |
| 50 | -264334 |
| 51 | 850990 |
| 52 | -1246504 |
| 53 | 1121960 |
| 54 | -711480 |
| 55 | 345268 |
| 56 | -135639 |
| 57 | 44997 |
| 58 | -12922 |
| 59 | 3171 |
| 60 | -644 |
| 61 | 119 |
| 62 | -28 |
| 63 | 7 |
| 64 | -1 |