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Square on the Inside

 Published on Saturday, 21st February 2015, 10:00 pm and solved by 3957
Difficulty: Level 6 [16%]

Problem 504

Let $ABCD$ be a quadrilateral whose vertices are lattice points lying on the coordinate axes as follows:

$A(a, 0)$, $B(0, b)$, $C(-c, 0)$, $D(0, -d)$, where $1 \le a, b, c, d \le m$ and $a, b, c, d, m$ are integers.

It can be shown that for $m = 4$ there are exactly $256$ valid ways to construct $ABCD$. Of these $256$ quadrilaterals, $42$ of them strictly contain a square number of lattice points.

How many quadrilaterals $ABCD$ strictly contain a square number of lattice points for $m = 100$?



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