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 | 1 |
| 3 | -2 |
| 4 | -11 |
| 5 | -24 |
| 6 | -8 |
| 7 | 141 |
| 8 | 573 |
| 9 | 1087 |
| 10 | -174 |
| 11 | -8700 |
| 12 | -31328 |
| 13 | -52740 |
| 14 | 36387 |
| 15 | 534198 |
| 16 | 1742445 |
| 17 | 2540583 |
| 18 | -3626189 |
| 19 | -33115232 |
| 20 | -97968686 |
| 21 | -118497822 |
| 22 | 301668764 |
| 23 | 2060526393 |
| 24 | 5526622320 |
| 25 | 5165256226 |
| 26 | -23033840842 |
| 27 | -127995025736 |
| 28 | -310560935969 |
| 29 | -193716799472 |