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A062670
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Composite and every divisor (except 1) contains the digit 4.
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18
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1849, 6407, 14227, 14309, 14921, 16403, 16441, 17243, 18409, 18847, 19049, 19147, 20459, 20941, 21457, 21479, 21949, 22427, 23453, 25427, 27649, 30409, 30463, 31949, 34921, 40463, 40721, 43009, 44227, 44509, 45107, 49303, 58343, 59491
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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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1849 has divisors 1, 43 and 1849, all of which contain the digit 4.
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MATHEMATICA
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fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 59500], !PrimeQ[#] && fQ[#, 4] &] (* Robert G. Wilson v, Jun 11 2014 *)
d4Q[n_]:=CompositeQ[n]&&AllTrue[Rest[Divisors[n]], DigitCount[#, 10, 4]>0&]; Select[Range[ 60000], d4Q] (* Harvey P. Dale, Jun 20 2023 *)
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CROSSREFS
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Cf. A062653, A062664, A062667, A062668, A062669, 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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