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A243819 Composite numbers n such that every divisor greater than one of n contains the digit 0. 3

%I #20 Nov 08 2019 03:18:05

%S 10201,10403,10609,10807,11009,11021,31007,40501,41303,41309,42907,

%T 43709,50803,51409,51809,60701,61307,61903,64307,65509,70801,71609,

%U 72203,73027,75007,76409,81709,91607,97049,101909,102313,102919,103121,103927,104131,104333,104339,104939,104957,105163,105949

%N Composite numbers n such that every divisor greater than one of n contains the digit 0.

%H Amiram Eldar, <a href="/A243819/b243819.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..2500 from Barbara W. Waddell and Robert G. Wilson v)

%e The divisors of 10201 are {1, 101, and 10201}. Except for 1 each has a 0 in its decimal expansion.

%t fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 106000], !PrimeQ[#] && fQ[#, 0] &]

%Y Cf. A062649, A062664, A062668, A062670, A062672, A062674, A062676, A062678, A062680.

%K nonn,base,easy

%O 1,1

%A Barbara W. Waddell and _Robert G. Wilson v_, Jun 11 2014

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Last modified April 19 09:23 EDT 2024. Contains 371782 sequences. (Running on oeis4.)