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A062668
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Composite and every divisor (except 1) contains the digit 3.
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17
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39, 93, 309, 339, 393, 403, 713, 933, 939, 993, 1137, 1293, 1317, 1329, 1333, 1339, 1369, 1389, 1643, 1703, 1839, 1893, 2263, 2319, 2369, 2573, 3013, 3029, 3039, 3071, 3093, 3099, 3107, 3117, 3139, 3151, 3189, 3193, 3197, 3279, 3309, 3369, 3419, 3459
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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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93 has divisors 1, 3, 31 and 93, all of which contain the digit 3.
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MATHEMATICA
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fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 3460], !PrimeQ[#] && fQ[#, 3] &] (* Robert G. Wilson v, Jun 11 2014 *)
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PROG
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(Magma) [k:k in [2..3500]| forall{d:d in Set(Divisors(k)) diff {1}| 3 in Intseq(d)}]; // Marius A. Burtea, Nov 07 2019
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CROSSREFS
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Cf. A062653, A062664, A062667, A062669, A062670, A062671, A062672, A062673, A062674, A062675, A062676, A062677, A062678, A062679, A062680.
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KEYWORD
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base,easy,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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