MathDB

E 32

Source:

May 25, 2007

LaTeX

Problem Statement

Let

n \ge 5

be an integer. Show that

n

is prime if and only if

n_{i} n_{j} \neq n_{p} n_{q}

for every partition of

n

into

4

integers,

n=n_{1}+n_{2}+n_{3}+n_{4}

, and for each permutation

(i, j, p, q)

of

(1, 2, 3, 4)

.

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