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 | 0 |
| 3 | 8 |
| 4 | -10 |
| 5 | -30 |
| 6 | 98 |
| 7 | 40 |
| 8 | -648 |
| 9 | 680 |
| 10 | 3058 |
| 11 | -8712 |
| 12 | -6760 |
| 13 | 65674 |
| 14 | -52710 |
| 15 | -348128 |
| 16 | 856358 |
| 17 | 1011330 |
| 18 | -7116754 |
| 19 | 3891920 |
| 20 | 41214978 |
| 21 | -87043088 |
| 22 | -143941360 |
| 23 | 793389048 |
| 24 | -224365750 |
| 25 | -4961373872 |
| 26 | 8914590594 |
| 27 | 19893652520 |
| 28 | -89559777800 |
| 29 | 540262170 |
| 30 | 601349934194 |
| 31 | -905363401312 |
| 32 | -2693832315240 |
| 33 | 10150582469480 |
| 34 | 2943320005570 |
| 35 | -73015796693016 |
| 36 | 89846661676688 |