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A095682
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Primitive 1+prime power perfect numbers: if n=Product p_i^r_i then 1PPsigma(n)= Product {Sum p_i^r_i, 1<=s_i<=r_i, s_i is one or prime} 1PPsigma(n)=2*n.
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0
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OFFSET
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1,1
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COMMENTS
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Factorizations: 2^2*3^2, 2^3*7^2, 2^5*3^2*23^2, 2^13*3^2*7^2*41^2, 2^7*3^5*5^2*29^2*47^2. No squarefree solution exists.
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LINKS
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EXAMPLE
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1PPsigma(2^5*3^3)=(2+2^2+2^3+2^5)*(3+3^2+3^3)=1794
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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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