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 | -3 |
| 3 | 6 |
| 4 | -4 |
| 5 | -15 |
| 6 | 54 |
| 7 | -87 |
| 8 | 63 |
| 9 | 79 |
| 10 | -405 |
| 11 | 912 |
| 12 | -1363 |
| 13 | 1193 |
| 14 | 510 |
| 15 | -4900 |
| 16 | 12512 |
| 17 | -21582 |
| 18 | 26512 |
| 19 | -16540 |
| 20 | -24585 |
| 21 | 113682 |
| 22 | -255045 |
| 23 | 419931 |
| 24 | -519210 |
| 25 | 377176 |
| 26 | 267957 |
| 27 | -1703694 |
| 28 | 4090424 |
| 29 | -7179222 |
| 30 | 9895981 |
| 31 | -9897664 |
| 32 | 3337614 |
| 33 | 14790666 |
| 34 | -49171217 |
| 35 | 100903743 |