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 | -1 |
| 2 | -2 |
| 3 | 10 |
| 4 | -25 |
| 5 | 33 |
| 6 | 57 |
| 7 | -561 |
| 8 | 2310 |
| 9 | -7150 |
| 10 | 18448 |
| 11 | -39168 |
| 12 | 55114 |
| 13 | 41990 |
| 14 | -726750 |
| 15 | 3657006 |
| 16 | -13846041 |
| 17 | 44907185 |
| 18 | -130605450 |
| 19 | 347227650 |
| 20 | -845335695 |
| 21 | 1842623895 |
| 22 | -3311675445 |
| 23 | 3271798125 |
| 24 | 9143639100 |
| 25 | -77910795756 |
| 26 | 356581496251 |
| 27 | -1331363100907 |
| 28 | 4430526577054 |
| 29 | -13595755404934 |
| 30 | 39119816049161 |
| 31 | -106498829726801 |
| 32 | 275433122695473 |
| 33 | -676162020887697 |
| 34 | 1563087628000497 |
| 35 | -3329539580829865 |
| 36 | 6175049600047825 |