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A229076
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Euler's fearsome foursome.
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1
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OFFSET
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1,1
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COMMENTS
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Four distinct positive integers the sum of any two of which is a square, two of the squares being equal.
Dunham calls them "Euler's fearsome foursome", but neglects to require that two of the sums be equal. Liu requires it and explains Euler's derivation.
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REFERENCES
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W. Dunham, Euler: The Master of Us All, MAA, 1999, p. 7.
L. Euler, Opera Omnia, vol. 5, pp. 337 - 339, supplement to Paper 796.
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LINKS
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EXAMPLE
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If (A, B, C, D) = (18530, 38114, 45986, 65570), then A+D = B+C = 290^2, A+C = 254^2, C+D = 334^2, A+B = 238^2, and B+D = 322^2.
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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