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 | 3 |
| 1 | 2 |
| 2 | 0 |
| 3 | 2 |
| 4 | -6 |
| 5 | 14 |
| 6 | -30 |
| 7 | 62 |
| 8 | -122 |
| 9 | 220 |
| 10 | -344 |
| 11 | 412 |
| 12 | -176 |
| 13 | -944 |
| 14 | 4112 |
| 15 | -11414 |
| 16 | 26254 |
| 17 | -53724 |
| 18 | 100710 |
| 19 | -175034 |
| 20 | 281660 |
| 21 | -410896 |
| 22 | 506846 |
| 23 | -391550 |
| 24 | -401486 |
| 25 | 2962260 |
| 26 | -9621128 |
| 27 | 24977308 |
| 28 | -57407998 |
| 29 | 120867310 |
| 30 | -236098336 |
| 31 | 428880422 |
| 32 | -719991244 |
| 33 | 1096219280 |