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A091935 Smallest number of 1's in binary representations of primes between 2^n and 2^(n+1). 4

%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

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Last modified October 23 22:28 EDT 2019. Contains 328373 sequences. (Running on oeis4.)