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Primes of the form Phi(k, -9), where Phi is the cyclotomic polynomial.
1

%I #9 Nov 11 2019 13:48:00

%S 73,530713,6481,47763361,42521761,150094634909578633,

%T 13490012358249728401,282429005041,

%U 19966781110160346782368664772328944885905284750420567849,1076050302914923449767311155851656076154481

%N Primes of the form Phi(k, -9), where Phi is the cyclotomic polynomial.

%H Robert Price, <a href="/A291991/b291991.txt">Table of n, a(n) for n = 1..13</a>

%H Yves Gallot, <a href="http://yves.gallot.pagesperso-orange.fr/papers/cyclotomic.html">Cyclotomic polynomials and prime numbers</a>

%H <a href="/index/Cy#CyclotomicPolynomialsValuesAtX">Index entries for cyclotomic polynomials,values at X</a>

%t Select[Table[Cyclotomic[k,-9], {k, 0, 100}], PrimeQ[#] &]

%Y Cf. A138921.

%K nonn

%O 1,1

%A _Robert Price_, Sep 07 2017