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A067226
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Numbers k such that phi(5k+1) = sigma(k).
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2
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5005, 6745, 79695, 99145, 160195, 166135, 296065, 350935, 486805, 960355, 1291105, 1350745, 1817365, 2218645, 2445685, 3287680, 4069135, 5341375, 5497965, 8933085, 14495065, 15106795, 16824535, 16850995, 18510055, 18710125, 21309085, 21521500, 22453345
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OFFSET
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1,1
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COMMENTS
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Are there any terms not congruent to 5 in the sequence?
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LINKS
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MATHEMATICA
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Select[Range[10^6], EulerPhi[5*# + 1] == DivisorSigma[1, #] &] (* Amiram Eldar, May 09 2022 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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