Task 722

Task 722: development task in emrekuruu/math-openenv, an RL environment on the Hugging Face Hub. If $a,$ $b,$ $x,$ and $y$ are real numbers such that $ax+by=3,$ $ax^2+by^2=7,$ $ax^3+by^3=16,$ and $ax^4+by^4=42,$ find $ax^5+by^5.$