%I #8 Nov 11 2019 13:56:21
%S 2801,43,16148168401,117307,11898664849,13564461457,6568801,
%T 29078814248401,13841169553,3421093417510114543,33232924804801,
%U 79787519018560501,1628413557556843,5457586804596062091175455674392801,402488219476647465854701
%N Primes of the form Phi(k, 7), where Phi is the cyclotomic polynomial.
%H Robert Price, <a href="/A292011/b292011.txt">Table of n, a(n) for n = 1..25</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,7], {k, 0, 100}], PrimeQ[#] &]
%Y Cf. A138937.
%K nonn
%O 1,1
%A _Robert Price_, Sep 07 2017