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%I #16 Sep 08 2022 08:45:03
%S 497,679,749,799,1207,1379,1739,1799,1897,2479,2627,2701,2779,3337,
%T 3713,3997,4607,4709,4711,4739,4757,4907,5173,5257,5327,5579,5729,
%U 5767,5789,6179,6749,6769,6797,6887,6979,7081,7169,7289,7379,7597,7609,7663
%N Composite and every divisor (except 1) contains the digit 7.
%H Amiram Eldar, <a href="/A062676/b062676.txt">Table of n, a(n) for n = 1..10000</a>
%e 799 has divisors 17, 47 and 799, all of which contain the digit 7.
%t fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 7670], !PrimeQ[#] && fQ[#, 7] &] (* _Robert G. Wilson v_, Jun 11 2014 *)
%o (Magma) [k:k in [2..8000]| not IsPrime(k) and forall{d:d in Set(Divisors(k)) diff {1}| 7 in Intseq(d)}];// _Marius A. Burtea_, Nov 07 2019
%Y Cf. A062653, A062664, A062667, A062668, A062669, A062670, A062671, A062672, A062673, A062674, A062675, 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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