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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A136418 Smallest order of the cyclotomic polynomial whose maximal coefficient in absolute value is n.

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%I A136418 #10 Apr 14 2017 02:59:45
%S A136418 0,105,385,1365,1785,2805,3135,10353,6545,12155,21385,11165,21505,
%T A136418 10465,16555,19285,37961,35105,18445,24395,23205,53669,11305,28595,
%U A136418 17255,36465,20615,42315,123585,31535,49335,39585,61295,35805,72709,54285
%N A136418 Smallest order of the cyclotomic polynomial whose maximal coefficient in absolute value is n.
%C A136418 This differs from A013594.
%C A136418 For squarefree k, are there an infinite number of cyclotomic polynomials Phi(k,x) of height n? This is true for n=1 because it is known that there are an infinite number of flat cyclotomic polynomials with k the product of three distinct primes. See A117223. - _T. D. Noe_, Apr 22 2008
%C A136418 There are an infinite number of cyclotomic polynomials of height n if the following generalization of Kaplan's theorem 2 is true: Let N be the product of distinct odd primes and let p be one of those primes. Let q any prime such that q = p (mod N/p), then the height of Phi(Nq/p,x) is the same as the height of Phi(N,x). By Dirichlet's theorem, there are an infinite number of primes q. [From _T. D. Noe_, Apr 13 2010]
%H A136418 T. D. Noe, <a href="/A136418/b136418.txt">Table of n, a(n) for n=1..1000</a>
%H A136418 Nathan Kaplan, <a href="https://doi.org/10.1016/j.jnt.2007.01.008">Flat cyclotomic polynomials of order three</a>, J. Number Theory 127 (2007), 118-126.
%t A136418 f[n_] := f[n] = Max@ Abs@ CoefficientList[ Cyclotomic[n, x], x]; Do[ f@n, {n, 100000}]; t = Array[f, 31000]; Table[ Position[t, n, 1, 1], {n, 25}]//Flatten
%Y A136418 Cf. A013594, A046887, A134518.
%K A136418 nonn
%O A136418 1,2
%A A136418 _Robert G. Wilson v_, Mar 31 2008
%E A136418 More terms from _T. D. Noe_, Apr 22 2008