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A015786
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Numbers k such that phi(k) + 7 | sigma(k + 7).
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3
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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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42 is a term in the sequence since phi(42) + 7 = 12 + 7 = 19 divides sigma(42 + 7) = 57.
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MATHEMATICA
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Select[Range[1000000], Divisible[DivisorSigma[1, # + 7], EulerPhi[#] + 7] &] (* Amiram Eldar, Dec 10 2018 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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