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 | -4 |
| 3 | -4 |
| 4 | 11 |
| 5 | 11 |
| 6 | -24 |
| 7 | -24 |
| 8 | 46 |
| 9 | 46 |
| 10 | -80 |
| 11 | -80 |
| 12 | 130 |
| 13 | 130 |
| 14 | -200 |
| 15 | -200 |
| 16 | 295 |
| 17 | 295 |
| 18 | -420 |
| 19 | -420 |
| 20 | 581 |
| 21 | 581 |
| 22 | -784 |
| 23 | -784 |
| 24 | 1036 |
| 25 | 1036 |
| 26 | -1344 |
| 27 | -1344 |
| 28 | 1716 |
| 29 | 1716 |
| 30 | -2160 |
| 31 | -2160 |
| 32 | 2685 |
| 33 | 2685 |
| 34 | -3300 |
| 35 | -3300 |
| 36 | 4015 |
| 37 | 4015 |
| 38 | -4840 |
| 39 | -4840 |
| 40 | 5786 |
| 41 | 5786 |
| 42 | -6864 |
| 43 | -6864 |
| 44 | 8086 |
| 45 | 8086 |
| 46 | -9464 |
| 47 | -9464 |
| 48 | 11011 |
| 49 | 11011 |
| 50 | -12740 |