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Search: id:A093894
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%I A093894
%S A093894 49,87,91,121,133,169,183,213,217,247,249,259,287,301,339,343,361,403,
%T A093894 411,427,445,469,473,481,501,511,527,529,553,559,581,589,591,633,679,
%U A093894 699,703,713,717,721,763,789,793,817,841,843,871,889,895,949,951,961
%N A093894 Composite members of A093893.
%C A093894 Comment: Most terms of this sequence have four divisors. Some (the prime 
               squares) have three divisors and very few terms have more than four 
               divisors (the first one is 4753, with six). Conjecture: This sequence 
               is infinite. - Adam M. Kalman (mocha(AT)clarityconnect.com), Nov 
               11 2004
%H A093894 Charles R. Greathouse IV, Sep 10, 2008, <a href="b093894.txt">Table of 
               n, a(n) for n = 1..10001</a>
%e A093894 133 is a member, the divisors are 1,7,19,133 and no sum of two or more 
               gives a prime.
%t A093894 For[a:=4, a<=2000, s =Divisors[a];n := 1;d := False; While[(n<=2^Length[s])\[And]( 
               ["not" character]d), If[Length[NthSubset[n, s]]>=2, If[ !PrimeQ[Plus@@NthSubset[n, 
               s]], n++, d:= True], n++ ]]; If[ ["not" character]d, Print[a]];a++;
               While[PrimeQ[a], a+=2]]; (Kalman)
%Y A093894 Cf. A093890, A093891, A093892, A093893.
%Y A093894 Sequence in context: A056938 A106311 A006832 this_sequence A158725 A090825 
               A157342
%Y A093894 Adjacent sequences: A093891 A093892 A093893 this_sequence A093895 A093896 
               A093897
%K A093894 nonn
%O A093894 1,1
%A A093894 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 23 2004
%E A093894 Corrected and extended by Adam M. Kalman (mocha(AT)clarityconnect.com), 
               Nov 11 2004

    
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Last modified November 29 12:46 EST 2009. Contains 167659 sequences.


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