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 | -2 |
| 2 | 3 |
| 3 | -3 |
| 4 | 1 |
| 5 | 4 |
| 6 | -12 |
| 7 | 21 |
| 8 | -26 |
| 9 | 19 |
| 10 | 9 |
| 11 | -63 |
| 12 | 136 |
| 13 | -200 |
| 14 | 201 |
| 15 | -66 |
| 16 | -269 |
| 17 | 805 |
| 18 | -1407 |
| 19 | 1740 |
| 20 | -1268 |
| 21 | -611 |
| 22 | 4230 |
| 23 | -9117 |
| 24 | 13393 |
| 25 | -13439 |
| 26 | 4368 |
| 27 | 18096 |
| 28 | -53999 |
| 29 | 94270 |
| 30 | -116445 |
| 31 | 84621 |
| 32 | 41473 |
| 33 | -284012 |
| 34 | 611172 |
| 35 | -896859 |
| 36 | 898534 |
| 37 | -289037 |
| 38 | -1217319 |
| 39 | 3622209 |
| 40 | -6316136 |
| 41 | 7792744 |
| 42 | -5647143 |
| 43 | -2814594 |