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A107746
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Numbers n such that the least prime factor of 6*n+1 > the least prime factor of 6*n-1, A107744(n) > A107745(n).
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3
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1, 2, 3, 5, 6, 7, 10, 11, 12, 13, 16, 17, 18, 20, 21, 23, 25, 26, 27, 30, 31, 32, 33, 35, 36, 37, 38, 40, 41, 45, 46, 47, 48, 51, 52, 55, 56, 58, 61, 62, 63, 66, 68, 70, 71, 72, 73, 76, 77, 81, 83, 86, 87, 88, 90, 91, 95, 96, 97, 100, 101, 102, 103, 105, 106, 107, 110, 111
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OFFSET
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1,2
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COMMENTS
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Complement of A107747 in the positive integers.
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LINKS
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MAPLE
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lpf:= n -> min(numtheory:-factorset(n)):
select(n -> lpf(6*n+1) > lpf(6*n-1), [$1..1000]); # Robert Israel, Oct 23 2015
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MATHEMATICA
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Select[Range@ 111, FactorInteger[6 # + 1][[1, 1]] > FactorInteger[6 # - 1][[1, 1]] &] (* Michael De Vlieger, Oct 23 2015 *)
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PROG
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(PARI) isok(n) = vecmin(factor(6*n+1)[, 1]) > vecmin(factor(6*n-1)[, 1]); \\ Michel Marcus, Feb 04 2014
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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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