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 | 4 |
| 2 | 13 |
| 3 | 31 |
| 4 | 40 |
| 5 | -23 |
| 6 | -95 |
| 7 | 490 |
| 8 | 823 |
| 9 | -8393 |
| 10 | 3766 |
| 11 | 174775 |
| 12 | -658787 |
| 13 | -2751404 |
| 14 | 34033297 |
| 15 | -55552037 |
| 16 | -1170734432 |
| 17 | 9362348365 |
| 18 | 3277050925 |
| 19 | -562286419646 |
| 20 | 3848880970147 |
| 21 | 8815342530739 |
| 22 | -356804325202730 |
| 23 | 2389771436686339 |
| 24 | 8677476137729929 |
| 25 | -302470260552857660 |