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A159225
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1/4 the number of n X n arrays of squares of integers with every 2X2 subblock summing to 25
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0
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7, 24, 53, 135, 265, 621, 1169, 2649, 4897, 10929, 20033, 44385, 81025, 178881, 325889, 718209, 1307137, 2878209, 5235713, 11523585, 20957185, 46115841, 83857409, 184506369, 335486977
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OFFSET
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2,1
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LINKS
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FORMULA
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Conjecture: G.f.: x^2*(-7-12*x^4+20*x^3+13*x^2-17*x)/((x-1)*(2*x+1)*(2*x-1)*(2*x^2-1)) [From Maksym Voznyy (voznyy(AT)mail.ru), Jul 26 2009]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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