FERMAT'S FOUR SQUARES THEOREM Several years ago, after

Solved {(x,y,z,w).M: x,y,z, w € Z} Theorem 8.35 (Lagrange's

Table 3 from Extended Lagrange's four-square theorem

Solved In Number Theory, Lagrange's four-square theorem

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

PDF) Extended Lagrange's four-square theorem

Lagrange's four-square theorem, polynomials, diophantine equations, prime numbers

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

Pythagorean Theorem

Four Square Theorem - Quaternions, PDF, Prime Number

Euler Four-Square Identity -- from Wolfram MathWorld