Euler's four-square identity - Wikipedia

PDF) A Simple Proof of Jacobi's Four-Square Theorem

Lagrange's Four-Square Theorem -- from Wolfram MathWorld

SOLVED: Theorem 8.35 (Lagrange's Four-Square Theorem) then n can be expressed as the sum If n is a number; of four squares: natural lattice A in 4-space is a set of the

PDF) Algebraic Consequences of Jacobi's Two- and Four-Square Theorems

Lagrange's Four Squares Theorem

Waring's Problem & Lagrange's Four-Square Theorem

Solved Lagrange's four square theorem says every natural

Lagrange's three square theorem

Sum of two squares theorem - Wikipedia

Stable/Patient Sort: Bit-Manipulation-To-Solve-Problems-Easily-And-Efficiently, PDF, Square Root