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 | 0 |
| 3 | 3 |
| 4 | -1 |
| 5 | 9 |
| 6 | -3 |
| 7 | 22 |
| 8 | -9 |
| 9 | 52 |
| 10 | -22 |
| 11 | 111 |
| 12 | -51 |
| 13 | 230 |
| 14 | -108 |
| 15 | 451 |
| 16 | -222 |
| 17 | 861 |
| 18 | -432 |
| 19 | 1587 |
| 20 | -819 |
| 21 | 2861 |
| 22 | -1501 |
| 23 | 5028 |
| 24 | -2691 |
| 25 | 8679 |
| 26 | -4707 |
| 27 | 14691 |
| 28 | -8089 |
| 29 | 24492 |
| 30 | -13638 |
| 31 | 40202 |
| 32 | -22653 |
| 33 | 65141 |
| 34 | -37060 |
| 35 | 104199 |
| 36 | -59863 |
| 37 | 164833 |
| 38 | -95484 |
| 39 | 257920 |
| 40 | -150646 |
| 41 | 399681 |
| 42 | -235141 |
| 43 | 613557 |
| 44 | -363543 |
| 45 | 933869 |