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 | 6 |
| 3 | -13 |
| 4 | 29 |
| 5 | -64 |
| 6 | 141 |
| 7 | -311 |
| 8 | 686 |
| 9 | -1513 |
| 10 | 3337 |
| 11 | -7360 |
| 12 | 16233 |
| 13 | -35803 |
| 14 | 78966 |
| 15 | -174165 |
| 16 | 384133 |
| 17 | -847232 |
| 18 | 1868629 |
| 19 | -4121391 |
| 20 | 9090014 |
| 21 | -20048657 |
| 22 | 44218705 |
| 23 | -97527424 |
| 24 | 215103505 |
| 25 | -474425715 |
| 26 | 1046378854 |
| 27 | -2307861213 |
| 28 | 5090148141 |
| 29 | -11226675136 |
| 30 | 24761211485 |
| 31 | -54612571111 |
| 32 | 120451817358 |