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A257413
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Values of n such that there are exactly 6 solutions to x^2 - y^2 = n with x > y >= 0.
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8
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240, 288, 315, 336, 360, 384, 432, 495, 504, 525, 528, 560, 585, 600, 624, 640, 675, 693, 735, 765, 792, 800, 816, 819, 825, 855, 880, 896, 912, 936, 975, 1035, 1040, 1071, 1104, 1125, 1176, 1197, 1215, 1224, 1232, 1260, 1275, 1287, 1305, 1323, 1360, 1368
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OFFSET
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1,1
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LINKS
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EXAMPLE
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240 is in the sequence because there are 6 solutions to x^2 - y^2 = 240, namely (x,y) = (16,4), (17,7), (19,11), (23,17), (32,28), (61,59).
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MATHEMATICA
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nn = 2000;
t = Table[0, {nn}];
Do[n = x^2 - y^2; If[n <= nn, t[[n]]++], {x, nn}, {y, 0, x - 1}];
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PROG
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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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