%I #10 Sep 30 2017 02:33:39
%S 1,3,5,7,17,27,51,91,183,309,617,1125,2097,3995
%N Number of zeros of the polynomial Sum_{j=0..n1} z^(2^j1)inside the unit circle.
%H Karl Dilcher and Larry Ericksen, <a href="http://www.jstor.org/stable/10.4169/amer.math.monthly.122.04.338">The Polynomials of Mahler and Roots of Unity</a>, The American Mathematical Monthly, Vol. 122, No. 04 (April 2015), pp. 338353.
%t Table[Length[Select[Flatten[Abs[z/.NSolve[Sum[z^(2^j1),{j,0,n1}]==0]]],#<1&]],{n,3,12}] (* _Vaclav Kotesovec_, May 17 2015, but for bigger n needs much memory (for n=14, 5 GB RAM) *)
%Y Cf. A257593.
%K nonn,more
%O 3,2
%A _N. J. A. Sloane_, May 15 2015
