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%I A073771
%S A073771 4,36,48,240,720,1680,15120,20160,45360,50400,221760,498960,554400,
%T A073771 665280,2882880,6486480,14414400,17297280,32432400,43243200,110270160,
%U A073771 245044800,294053760,735134400,2095133040,2205403200,4655851200
%N A073771 Highly composite numbers n such that 2*n is not a highly composite number.
%C A073771 The terms were determined by means of A. Flammenkamp's list (cf. Links), 
               the terms <= 17297280 were confirmed by a PARI program.
%H A073771 Achim Flammenkamp <a href="http://www.uni-bielefeld.de/~achim/highly.html">
               Highly Composite Numbers</a>
%e A073771 36 = A002182(7) is a term since 2*36 = 72 is not highly composite.
%o A073771 (PARI) {a=1; v=[1]; for(k=1,40000000,b=numdiv(k); if(b>a,a=b; v=concat(v,
               k); while(2*v[1]<=k,if(2*v[1]<k,print1(v[1],",")); v=vecextract(v,
               "2.."))))}
%Y A073771 Cf. A002182, A072938.
%Y A073771 Sequence in context: A144162 A027644 A062182 this_sequence A091722 A053939 
               A167632
%Y A073771 Adjacent sequences: A073768 A073769 A073770 this_sequence A073772 A073773 
               A073774
%K A073771 nonn
%O A073771 1,1
%A A073771 Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Aug 19 2002

    
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Last modified December 7 23:50 EST 2009. Contains 170430 sequences.


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