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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
 1, 3, 5, 7, 17, 27, 51, 91, 183, 309, 617, 1125, 2097, 3995 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,2 LINKS Table of n, a(n) for n=3..16. Karl Dilcher and Larry Ericksen, The Polynomials of Mahler and Roots of Unity, The American Mathematical Monthly, Vol. 122, No. 04 (April 2015), pp. 338-353. MATHEMATICA 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) *) CROSSREFS Cf. A257593. Sequence in context: A086086 A141772 A220454 * A032496 A002092 A274906 Adjacent sequences: A257589 A257590 A257591 * A257593 A257594 A257595 KEYWORD nonn,more AUTHOR N. J. A. Sloane, May 15 2015 STATUS approved

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Last modified September 23 17:42 EDT 2023. Contains 365554 sequences. (Running on oeis4.)