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 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | -1 |
| 4 | 0 |
| 5 | 2 |
| 6 | -3 |
| 7 | 1 |
| 8 | 4 |
| 9 | -8 |
| 10 | 5 |
| 11 | 7 |
| 12 | -20 |
| 13 | 18 |
| 14 | 9 |
| 15 | -47 |
| 16 | 56 |
| 17 | 0 |
| 18 | -103 |
| 19 | 159 |
| 20 | -56 |
| 21 | -206 |
| 22 | 421 |
| 23 | -271 |
| 24 | -356 |
| 25 | 1048 |
| 26 | -963 |
| 27 | -441 |
| 28 | 2452 |
| 29 | -2974 |
| 30 | 81 |
| 31 | 5345 |
| 32 | -8400 |
| 33 | 3136 |
| 34 | 10609 |
| 35 | -22145 |
| 36 | 14672 |
| 37 | 18082 |
| 38 | -54899 |
| 39 | 51489 |
| 40 | 21492 |
| 41 | -127880 |
| 42 | 157877 |
| 43 | -8505 |
| 44 | -277252 |
| 45 | 443634 |
| 46 | -174887 |
| 47 | -545999 |
| 48 | 1164520 |
| 49 | -793408 |
| 50 | -917111 |