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Every rectangle is formed from a number of full squares

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September 22, 2010
geometryrectanglecombinatoricsIMOIMO 1974Chessboarddissection

Problem Statement

We consider the division of a chess board 8×88 \times 8 in p disjoint rectangles which satisfy the conditions:
a) every rectangle is formed from a number of full squares (not partial) from the 64 and the number of white squares is equal to the number of black squares.
b) the numbers  a1,,ap\ a_{1}, \ldots, a_{p} of white squares from pp rectangles satisfy a1,,,ap.a_1, , \ldots, a_p. Find the greatest value of pp for which there exists such a division and then for that value of p,p, all the sequences a1,,apa_{1}, \ldots, a_{p} for which we can have such a division.
[color=#008000]Moderator says: see https://artofproblemsolving.com/community/c6h58591