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%I A144043
%S A144043 2,3,4,5,6,8,10,12,14,18,22,24,26,30,34,36,38,42,46
%N A144043 Sum of the middle pair as the prime sequence unfolds
%C A144043 An exotic sequence with a tantalizing non-regularity. It is strictly 
               nondecreasing (very easy to show). The first order differences (1, 
               1, 1, 1, 2, 2, 2, 2, 4, 4, 2, 2, 4, 4, 2, 2, 4, 4, ...) are also 
               very erratic.
%e A144043 2= sumtwice(1) 3= sum(1,2) 4= 1, sumtwice(2), 3 5= 1, sum(2,3), 5 6= 
               1, 2, sumtwice(3), 5, 7 8= 1,2, sum(3,5), 7, 11
%o A144043 (Other) %Matlab source code clc clear all aP= [1, primes(1000)]; qN= 
               numel(aP); kL=[]; %init empty result for nn= 1:qN %Loop to sum the 
               central pairs auxT= ceil((nn+1)/2); auxL= ceil(nn/2); kL= [kL; aP(auxL)+aP(auxT)]; 
               end kL %kL is the result
%Y A144043 Sequence in context: A056864 A029032 A059809 this_sequence A121492 A078931 
               A003401
%Y A144043 Adjacent sequences: A144040 A144041 A144042 this_sequence A144044 A144045 
               A144046
%K A144043 easy,nonn
%O A144043 1,1
%A A144043 Raul Rato (rtrato(AT)yahoo.com), Sep 08 2008

    
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Last modified December 17 19:39 EST 2009. Contains 170821 sequences.


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