Enumeration of $4 \times 4$ magic squares
2010; American Mathematical Society; Volume: 80; Issue: 273 Linguagem: Inglês
10.1090/s0025-5718-10-02347-1
ISSN1088-6842
AutoresMatthias Beck, Andrew van Herick,
Tópico(s)Advanced Combinatorial Mathematics
ResumoA magic square is an $n \times n$ array of distinct positive integers whose sum along any row, column, or main diagonal is the same number. We compute the number of such squares for $n=4$, as a function of either the magic sum or an upper bound on the entries. The previous record for both functions was the $n=3$ case. Our methods are based on inside-out polytopes, i.e., the combination of hyperplane arrangements and Ehrhartâs theory of lattice-point enumeration.
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