%I A086904
%S A086904 1,1,2,7,13,35,71
%N A086904 Write the primes in binary; a(n) = total number of 0's in those which 
               have an n-bit expansion.
%e A086904 a(2) = 1: 1 = 10 and 3 = 11, with a total of one 0. a(3) = 1: 5 = 101, 
               7 = 111, again with just one 0.
%Y A086904 Sequence in context: A127396 A079119 A051748 this_sequence A026555 A129592 
               A153136
%Y A086904 Adjacent sequences: A086901 A086902 A086903 this_sequence A086905 A086906 
               A086907
%K A086904 base,nonn
%O A086904 2,3
%A A086904 Jacob Woolcutt (woolcutt(AT)uiuc.edu), Sep 19 2003