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A122225
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(1/4)*number of nonsquare rectangles with corners on an n X n grid of points.
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1
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1, 6, 20, 52, 111, 214, 376, 620, 967, 1452, 2096, 2952, 4047, 5422, 7128, 9236, 11773, 14834, 18450, 22704, 27675, 33460, 40090, 47708, 56383, 66214, 77276, 89748, 103647, 119206, 136476, 155592, 176681, 199858, 225224, 253104, 283555, 316692
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OFFSET
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3,2
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LINKS
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FORMULA
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EXAMPLE
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a(3)=1 because there are 4 rectangles that can be formed on the square grid [0,1,2] X [0,1,2]: {(0 0),(0 1),(2 0),(2 1)}, {(0 0),(0 2),(1 0),(1 2)}, {(0 1),(0 2),(2 1),(2 2)}, {(1 0),(1 2),(2 0),(2 2)}.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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