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Source labels openChecked July 26, 2026

WikipediaCombinatorics

Magic Squares

Does there exist a 3×33 \times 3 semi-magic square whose entries are all distinct positive integer cubes? A square is semi-magic if all rows and columns sum to the same total.

Mathematical statement

Does there exist a 3×33 \times 3 semi-magic square whose entries are all distinct positive integer cubes? A square is semi-magic if all rows and columns sum to the same total.

More precisely, we seek a 3×33 \times 3 matrix with entries aija_{ij} such that each aij=nij3a_{ij} = n_{ij}^3 for some positive integer nijn_{ij}, all nine cubes are distinct, and all row sums and column sums are equal. Reference:* Semi-Magic Square of Cubes

Statement source: Wikipedia statement material

Statement terms: Source-specific

Source-specific terms. Therefore does not assert reuse rights beyond attributed display.

Statement artifacts, not proofs

These records expose exact Lean propositions and statement-only wrappers. Defining a proposition does not supply a proof of it. A placeholder-bearing target also contains no proof. Elaboration checks syntax and types; it does not certify that a formalization perfectly captures every nuance of the informal problem.

Pinned Lean formulation 1

exists_semi_magic_square_cubes

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem exists_semi_magic_square_cubes :    answer(sorry)   m : Fin 3  Fin 3  ,  t : ,       m.Injective2        ( i j,  n : , 0 < n  m i j = n ^ 3)        ( i, ∑ j, m i j = t)        ( j, ∑ i, m i j = t) := by  sorry
Statement source
Formal Conjectures
Lean version
v4.27.0
Placeholder
Present; no proof artifact
Source evidence
Pinned source index
Fidelity review
Community formulation

References