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

Lagrange’s four-square theorem, in number theory, theorem that every positive integer can be expressed as the sum of the squares of four integers. For example, 23 = 12 + 22 + 32 + 32. The four-square theorem was first proposed by the Greek mathematician Diophantus of Alexandria in his treatise

Lagrange's four-square theorem - Wikipedia

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Lagrange's four-square theorem - Wikipedia

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Table 3 from Extended Lagrange's four-square theorem

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PDF) Equilateral Triangles in ℤ4

Table 1 from Extended Lagrange's four-square theorem