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 | 0 |
| 2 | 6 |
| 3 | -6 |
| 4 | 20 |
| 5 | -36 |
| 6 | 50 |
| 7 | -114 |
| 8 | 104 |
| 9 | -264 |
| 10 | 190 |
| 11 | -510 |
| 12 | 316 |
| 13 | -876 |
| 14 | 490 |
| 15 | -1386 |
| 16 | 720 |
| 17 | -2064 |
| 18 | 1014 |
| 19 | -2934 |
| 20 | 1380 |
| 21 | -4020 |
| 22 | 1826 |
| 23 | -5346 |
| 24 | 2360 |
| 25 | -6936 |
| 26 | 2990 |
| 27 | -8814 |
| 28 | 3724 |
| 29 | -11004 |
| 30 | 4570 |
| 31 | -13530 |
| 32 | 5536 |
| 33 | -16416 |
| 34 | 6630 |
| 35 | -19686 |
| 36 | 7860 |
| 37 | -23364 |
| 38 | 9234 |
| 39 | -27474 |
| 40 | 10760 |
| 41 | -32040 |
| 42 | 12446 |
| 43 | -37086 |
| 44 | 14300 |
| 45 | -42636 |
| 46 | 16330 |