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A066684
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Numbers k such that prime(k) is congruent to sigma(k) (mod k), where prime(n) denotes the n-th prime.
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0
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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prime(5) = 11 is congruent to sigma(5) = 6 (mod 5), so 5 is in the sequence.
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MATHEMATICA
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Select[ Range[ 1, 10^5 ], Mod[ DivisorSigma[ 1, # ], # ] == Mod[ Prime[ # ], # ] & ]
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CROSSREFS
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KEYWORD
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nonn,hard,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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