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%I #7 Apr 15 2020 06:53:56
%S 2,9,448,21025,25566816,13167792001,374186407100416,
%T 2185268430227969025,1406243047344105338882560,
%U 95493100905174500882676787201,1357963145594500259453732165378899968,1093895614508277127564115719556899066650625
%N Resultant of the polynomial x^n-1 and the Chebyshev polynomial of the second kind U_n(x).
%H Andrew Howroyd, <a href="/A085605/b085605.txt">Table of n, a(n) for n = 1..50</a>
%t Table[Resultant[x^n - 1, ChebyshevU[n, x], x], {n, 1, 15}] (* _Vaclav Kotesovec_, Apr 15 2020 *)
%o (PARI) a(n)={polresultant(x^n-1, polchebyshev(n, 2, x))} \\ _Andrew Howroyd_, Jul 10 2018
%Y Cf. A086840.
%K nonn
%O 1,1
%A Yuval Dekel (dekelyuval(AT)hotmail.com), Aug 15 2003
%E Terms a(7) and beyond from _Andrew Howroyd_, Jul 10 2018