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A175556
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Numbers n such that n^7 is the sum of a positive fifth power and a square: n^7=x^5+y^2, with repetition.
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1
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8, 9, 98, 108, 125, 196, 225, 576, 676, 864, 900, 1000, 1352, 1568, 1568, 1764, 2000, 2601, 3087, 3993, 4232, 4418, 4913, 5324, 5400, 6348, 7225, 7776, 8100, 8100, 8192, 9216, 12348, 12482, 15123, 15376, 15552, 16464, 16928, 17576, 18225
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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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8^7=16^5+1024^2=2097152, 9^7=18^5+1701^2=4782969.
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PROG
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(PARI) a175556_print(n) = {local(xm, n7, r, x); if(n < 2, return(0)); xm = floor(n^(7/5)); n7 = n^7; for(x = 1, xm, r = n7 - x^5; if(issquare(r) && r > 0, print(n)))} \\ Michael B. Porter, Sep 22 2015
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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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