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 | 3 |
| 2 | 7 |
| 3 | 11 |
| 4 | 7 |
| 5 | -5 |
| 6 | 23 |
| 7 | 75 |
| 8 | -281 |
| 9 | -101 |
| 10 | 4663 |
| 11 | -14229 |
| 12 | -41721 |
| 13 | 532667 |
| 14 | -1464489 |
| 15 | -8840053 |
| 16 | 103689511 |
| 17 | -313202725 |
| 18 | -2348557705 |
| 19 | 32041266859 |
| 20 | -127039882425 |
| 21 | -762423051013 |
| 22 | 14393151011735 |
| 23 | -81523161874741 |
| 24 | -236027974047897 |
| 25 | 8564406463119387 |