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 | -5 |
| 2 | 5 |
| 3 | 0 |
| 4 | 30 |
| 5 | -51 |
| 6 | 5 |
| 7 | -130 |
| 8 | 220 |
| 9 | -125 |
| 10 | 649 |
| 11 | -605 |
| 12 | 870 |
| 13 | -2695 |
| 14 | 1565 |
| 15 | -4852 |
| 16 | 7915 |
| 17 | -6360 |
| 18 | 20625 |
| 19 | -17880 |
| 20 | 33551 |
| 21 | -61015 |
| 22 | 50865 |
| 23 | -138510 |
| 24 | 135485 |
| 25 | -224725 |
| 26 | 389025 |
| 27 | -359610 |
| 28 | 849525 |
| 29 | -838970 |
| 30 | 1417404 |
| 31 | -2195205 |
| 32 | 2275690 |
| 33 | -4756040 |
| 34 | 4657940 |
| 35 | -8315123 |
| 36 | 11174840 |
| 37 | -13352315 |