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 A257592 Number of zeros of the polynomial Sum_{j=0..n-1} z^(2^j-1)inside the unit circle. 1

%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..n-1} z^(2^j-1)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. 338-353.

%t Table[Length[Select[Flatten[Abs[z/.NSolve[Sum[z^(2^j-1),{j,0,n-1}]==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

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Last modified December 5 04:31 EST 2023. Contains 367574 sequences. (Running on oeis4.)