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Every divisor (except 1) contains the digit 6.
18

%I #15 Sep 08 2022 08:45:03

%S 61,67,163,167,263,269,367,461,463,467,563,569,601,607,613,617,619,

%T 631,641,643,647,653,659,661,673,677,683,691,761,769,863,967,1061,

%U 1063,1069,1163,1361,1367,1567,1601,1607,1609,1613,1619,1621,1627,1637,1657

%N Every divisor (except 1) contains the digit 6.

%H Amiram Eldar, <a href="/A062673/b062673.txt">Table of n, a(n) for n = 1..10000</a>

%e 26569 has divisors 163 and 26569, each of which contains the digit 6.

%t fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 1660], fQ[#, 6] &] (* _Robert G. Wilson v_, Jun 11 2014 *)

%o (Magma) [k:k in [2..1700]| forall{d:d in Set(Divisors(k)) diff {1}| 6 in Intseq(d)}];// _Marius A. Burtea_, Nov 07 2019

%Y Cf. A062653, A062664, A062667, A062668, A062669, A062670, A062671, A062672, 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