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%I #19 Sep 08 2022 08:45:03
%S 2,23,29,127,211,223,227,229,233,239,241,251,254,257,263,269,271,277,
%T 281,283,293,421,422,482,502,521,523,526,529,542,562,727,821,823,827,
%U 829,842,929,1021,1042,1123,1129,1201,1213,1217,1223,1229,1231,1237
%N Every divisor (except 1) contains the digit 2.
%H Amiram Eldar, <a href="/A062653/b062653.txt">Table of n, a(n) for n = 1..10000</a>
%e 254 has divisors 1, 2, 127 and 254, all of which contain the digit 2.
%t fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 1300], fQ[#, 2] &] (* _Robert G. Wilson v_, Jun 11 2014 *)
%o (Magma) [k:k in [2..1300]| forall{d:d in Set(Divisors(k)) diff {1}| 2 in Intseq(d)}]; // _Marius A. Burtea_, Nov 07 2019
%o (PARI) has2(n)=if(n==1, return(1)); !!setsearch(Set(digits(n)),2)
%o is(n)=fordiv(n,d, if(!has2(d), return(0))); 1 \\ _Charles R Greathouse IV_, Jan 24 2020
%Y Cf. A062664, A062667, A062668, A062669, A062670, 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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