%I
%S 1,2,3,2,3,3,3,2,3,3,3,3,3,3,3,2,3,3,3,3,3,3,3,3,4,3,3,3,3,3,3,4,3,3,
%T 3,3,3,3,3,4,3,3,4,3,3,3,3,4,3,3,3,3,3,3,3,4,3,4,3,3,3,3,3,4,3,3,3,3,
%U 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,3,3,3,3,3,3,3,4,3
%N Smallest number of 1's in binary representations of primes between 2^n and 2^(n+1).
%C a(n) = A000120(A091936(n)).
%C 0 never appears, 1 appears only at 1, 2's appear only for Fermat primes (A019434), 4's appear at A092100. I have found no fives <= 250.  _Robert G. Wilson v_
%t Run the second Mathematica line of A091936, then Join[{1}, Count[ IntegerDigits[ #, 2], 1] & /@ Table[ f[n], {n, 2, 105}]] (* _Robert G. Wilson v_, Feb 19 2004 *)
%Y Cf. A091937, A092100.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Feb 14 2004
%E More terms from _Robert G. Wilson v_, Feb 18 2004
