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%I #15 Jun 20 2023 14:50:18
%S 1849,6407,14227,14309,14921,16403,16441,17243,18409,18847,19049,
%T 19147,20459,20941,21457,21479,21949,22427,23453,25427,27649,30409,
%U 30463,31949,34921,40463,40721,43009,44227,44509,45107,49303,58343,59491
%N Composite and every divisor (except 1) contains the digit 4.
%H Amiram Eldar, <a href="/A062670/b062670.txt">Table of n, a(n) for n = 1..10000</a>
%e 1849 has divisors 1, 43 and 1849, all of which contain the digit 4.
%t 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 *)
%t d4Q[n_]:=CompositeQ[n]&&AllTrue[Rest[Divisors[n]],DigitCount[#,10,4]>0&]; Select[Range[ 60000],d4Q] (* _Harvey P. Dale_, Jun 20 2023 *)
%Y Cf. A062653, A062664, A062667, A062668, A062669, A062671, A062672, A062673, A062674, A062675, A062676, A062677, A062678, A062679, A062680.
%K base,easy,nonn
%O 1,1
%A _Erich Friedman_, Jul 04 2001
%E Offset corrected by _Amiram Eldar_, Nov 07 2019
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