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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A062679 Numbers such that every divisor (except 1, but including the number itself) contains the digit 9.

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