%I A056973
%S A056973 0,0,0,1,0,0,0,2,1,0,0,1,0,0,0,3,2,1,1,1,0,0,0,2,1,0,0,1,0,0,0,4,3,2,
%T A056973 2,2,1,1,1,2,1,0,0,1,0,0,0,3,2,1,1,1,0,0,0,2,1,0,0,1,0,0,0,5,4,3,3,3,
%U A056973 2,2,2,3,2,1,1,2,1,1,1,3,2,1,1,1,0,0,0,2,1,0,0,1,0,0,0,4,3,2,2,2,1,1
%N A056973 Number of blocks of {0,0} in the binary expansion of n.
%H A056973 R. Stephan, <a href="somedcgf.html">Some divide-and-conquer sequences 
               ...</a>
%H A056973 R. Stephan, <a href="a079944.ps">Table of generating functions</a>
%H A056973 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               DigitBlock.html">Link to a section of The World of Mathematics.</
               a>
%F A056973 a(2n) = a(n) + [n is even], a(2n+1) = a(n).
%F A056973 G.f.: 1/(1-x) * sum(k>=0, t^4/(1+t)/(1+t^2), t=x^2^k). - Ralf Stephan 
               (ralf(AT)ark.in-berlin.de), Sep 10 2003
%F A056973 a(n) = A023416(n) - A033264(n). - Ralf Stephan (ralf(AT)ark.in-berlin.de), 
               Sep 10 2003
%Y A056973 Cf. A014081, A033264, A037800.
%Y A056973 Sequence in context: A066301 A046660 A108730 this_sequence A107782 A086017 
               A000161
%Y A056973 Adjacent sequences: A056970 A056971 A056972 this_sequence A056974 A056975 
               A056976
%K A056973 nonn
%O A056973 1,8
%A A056973 Eric Weisstein (eric(AT)weisstein.com)