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A197917
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Suppose n has prime factorization n=p1^a1*p2^a2*...*pk^ak and that D(n) is A006218, then n has all D(ai) even.
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0
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1, 16, 32, 64, 81, 128, 243, 256, 625, 729, 1296, 2187, 2401, 2592, 3125, 3888, 5184, 6561, 7776, 10000, 10368, 11664, 14641, 15552, 15625, 16807, 20000, 20736, 23328, 28561, 31104, 34992, 38416, 40000, 46656, 50000, 50625, 62208, 65536, 69984, 76832, 78125
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OFFSET
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1,2
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COMMENTS
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Equivalently, for all exponents e in the factorization of n, floor(sqrt(e)) is even. [Charles R Greathouse IV, Oct 20 2011]
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LINKS
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PROG
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(PARI) is(n)=my(f=factor(n)[, 2]); for(i=1, #f, if(sqrtint(f[i])%2, return(0))); 1 \\ Charles R Greathouse IV, Oct 20 2011
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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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