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%I A144079
%S A144079 1,0,2,1,3,1,3,2,4,0,2,0,2,2,4,3,5,1,3,3,5,1,3,1,3,3,5,1,3,3,5,4,6,2,4,
%T A144079 2,4,0,2,2,4,0,2,4,6,2,4,2,4,4,6,0,2,2,4,0,2,2,4,2,4,4,6,5,7,3,5,3,5,1,
%U A144079 3,5,7,3,5,3,5,1,3,3,5,1,3,5,7,3,5,3,5,1,3,5,7,3,5,3,5,5,7,1,3,3,5,3,5
%N A144079 a(n) = the number of digits in the binary representation of n that each 
               equal the respective digit in the binary reversal of n. (ie a(n) 
               = number of 0's in n XOR A030101(n).)
%C A144079 A144078(n) + A144079(n) = A070939(n), the number of binary digits in 
               n.
%H A144079 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> 
               (listed in lieu of email address)
%e A144079 20 in binary is 10100. Compare this with its digit reversal, 00101. XOR 
               each pair of respective digits: 1 XOR 0 = 1, 0 XOR 0 = 0, 1 XOR 1 
               = 0, 0 XOR 0 = 0, 0 XOR 1 = 1. There are three bit pairs that contain 
               the same values, so a(20) = 3.
%p A144079 A144079 := proc(n) local a,dgs,i; a := 0 ; dgs := convert(n,base,2) ; 
               for i from 1 to nops(dgs) do if op(i,dgs)+op(-i,dgs) <> 1 then a 
               := a+1 ; fi; od; RETURN(a) ; end: for n from 1 to 240 do printf("%d,
               ",A144079(n)) ; od: [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), 
               Sep 14 2008]
%Y A144079 A030101, A144078
%Y A144079 Sequence in context: A109698 A029231 A025808 this_sequence A071575 A038569 
               A020650
%Y A144079 Adjacent sequences: A144076 A144077 A144078 this_sequence A144080 A144081 
               A144082
%K A144079 base,nonn
%O A144079 1,3
%A A144079 Leroy Quet Sep 09 2008
%E A144079 More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 14 2008

    
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Last modified December 5 23:38 EST 2009. Contains 170428 sequences.


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