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 | 0 |
| 4 | -2 |
| 5 | -6 |
| 6 | -10 |
| 7 | -13 |
| 8 | -10 |
| 9 | 4 |
| 10 | 36 |
| 11 | 84 |
| 12 | 137 |
| 13 | 159 |
| 14 | 94 |
| 15 | -133 |
| 16 | -573 |
| 17 | -1197 |
| 18 | -1788 |
| 19 | -1864 |
| 20 | -647 |
| 21 | 2741 |
| 22 | 8784 |
| 23 | 16631 |
| 24 | 22920 |
| 25 | 20769 |
| 26 | 87 |
| 27 | -49372 |
| 28 | -130497 |
| 29 | -226511 |
| 30 | -286165 |
| 31 | -214344 |
| 32 | 117678 |
| 33 | 822398 |
| 34 | 1889427 |
| 35 | 3022590 |
| 36 | 3465187 |
| 37 | 1927286 |
| 38 | -3188290 |
| 39 | -13016609 |
| 40 | -26739085 |