VMO 2005 Problem 4

Find all function $f: \mathbb R\to \mathbb R$ satisfying the condition: $f(f(x - y)) = f(x)\cdot f(y) - f(x) + f(y) - xy$

Dataset text AI-MO AoPS. Quoted with source.

Solutions

No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.