Formal target: Corpus.OEIS281976.conjecture
**Zhi-Wei Sun's Conjecture (A281976)**: Any integer $n \geq 0$ can be written as $x^2 + y^2 + z^2 + w^2$ with $x, y, z, w$ nonnegative integers and $z \leq w$, such that both $x$ and $x + 24y$ are squares.
Exact formal statement
∀ (n : Nat), Corpus.OEIS281976.A nThis target is a formal statement, not a proof of the problem.
Environment availability: available.