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A243582
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Integers of the form 8k+7 (A004771) that cannot be written as sum of four distinct squares.
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5
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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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a(6) = 55 since 55 == 7 (mod 8) and all its representations as a sum of squares have duplicates, namely, 55=1^2+1^2+2^2+7^2, 55=1^2+2^2+5^2+5^2, 55=1^2+3^2+3^2+6^2.
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CROSSREFS
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Cf. A001948, A004771, A008586, A016813, A016825, A004767, A243577, A243578, A243579, A243580, A243581.
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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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