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A062677 Numbers with property that every divisor (except 1) contains the digit 8.

%I A062677 #25 Nov 07 2019 05:19:04
%S A062677 83,89,181,281,283,383,389,487,587,683,787,809,811,821,823,827,829,
%T A062677 839,853,857,859,863,877,881,883,887,983,1087,1181,1187,1283,1289,
%U A062677 1381,1481,1483,1487,1489,1583,1783,1787,1789,1801,1811,1823,1831,1847,1861
%N A062677 Numbers with property that every divisor (except 1) contains the digit 8.
%C A062677 Subsequence of A011538, numbers with an 8. - _Michel Marcus_, Nov 21 2015
%H A062677 Amiram Eldar, <a href="/A062677/b062677.txt">Table of n, a(n) for n = 1..10000</a>
%e A062677 7387 has divisors 83, 89 and 7387, all of which contain the digit 8.
%p A062677 isA062677 := proc(n)
%p A062677     if n = 1 then
%p A062677         return false;
%p A062677     end if;
%p A062677     for d in numtheory[divisors](n) minus {1} do
%p A062677         convert(convert(d,base,10),set) ;
%p A062677         if  not 8 in % then
%p A062677             return false;
%p A062677         end if;
%p A062677     end do:
%p A062677     true ;
%p A062677 end proc:
%p A062677 for n from 1 to 2000 do
%p A062677     if isA062677(n) then
%p A062677         printf("%d,",n) ;
%p A062677     end if;
%p A062677 end do: # _R. J. Mathar_, Mar 27 2017
%t A062677 fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 1900], fQ[#, 8] &] (* _Robert G. Wilson v_, Jun 11 2014 *)
%Y A062677 Cf. A062653, A062664, A062667, A062668, A062669, A062670, A062671, A062672, A062673, A062674, A062675, A062676, A062678, A062679, A062680.
%K A062677 base,easy,nonn
%O A062677 1,1
%A A062677 _Erich Friedman_, Jul 04 2001