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) |
|---|---|
| 2 | 1 |
| 3 | 0 |
| 4 | 9 |
| 5 | -6 |
| 6 | 54 |
| 7 | -54 |
| 8 | 264 |
| 9 | -324 |
| 10 | 1127 |
| 11 | -1534 |
| 12 | 4338 |
| 13 | -6274 |
| 14 | 15372 |
| 15 | -22986 |
| 16 | 50846 |
| 17 | -77448 |
| 18 | 158599 |
| 19 | -243696 |
| 20 | 470206 |
| 21 | -724576 |
| 22 | 1333275 |
| 23 | -2052498 |
| 24 | 3634077 |
| 25 | -5575498 |
| 26 | 9561408 |
| 27 | -14596950 |
| 28 | 24368133 |
| 29 | -36983308 |
| 30 | 60336459 |
| 31 | -90983536 |
| 32 | 145510968 |
| 33 | -217948138 |
| 34 | 342546543 |
| 35 | -509567136 |
| 36 | 788639494 |