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%I #29 Sep 08 2022 08:45:03
%S 19,29,59,79,89,97,109,139,149,179,191,193,197,199,229,239,269,293,
%T 349,359,379,389,397,409,419,439,449,479,491,499,509,569,593,599,619,
%U 659,691,709,719,739,769,797,809,829,839,859,907,911,919,929,937,941,947
%N Numbers such that every divisor (except 1, but including the number itself) contains the digit 9.
%C Different from A106093. 1691 = 19 * 89 is the smallest term that is not in A106093. - _Franklin T. Adams-Watters_, Apr 30 2007
%H Amiram Eldar, <a href="/A062679/b062679.txt">Table of n, a(n) for n = 1..10000</a>
%e 7961 has divisors 19, 419 and 7961, all of which contain the digit 9.
%t fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 1000], fQ[#, 9] &] (* _Robert G. Wilson v_, Jun 11 2014 *)
%t d9Q[n_]:=First[Union[DigitCount[#,10,9]&/@Rest[Divisors[n]]]]>0; Select[ Range[ 2,1000],d9Q] (* _Harvey P. Dale_, Sep 12 2014 *)
%o (PARI) isok(n) = {if (n==1, return (0)); d = divisors(n); for (k=1, #d, if ((d[k] != 1) && (vecmax(digits(d[k])) != 9), return (0));); return (1);} \\ _Michel Marcus_, Nov 21 2015
%o (Magma) [n: n in [2..1000] | forall{Divisors(n)[i]: i in [2..NumberOfDivisors(n)] | 9 in Intseq(Divisors(n)[i])}]; // _Bruno Berselli_, Nov 21 2015
%Y Cf. A062653, A062664, A062667, A062668, A062669, A062670, A062671, A062672, A062673, A062674, A062675, A062676, A062677, A062678, A062680.
%K base,easy,nonn
%O 1,1
%A _Erich Friedman_, Jul 04 2001
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