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%I #16 Apr 12 2019 08:24:43
%S 241,409,1201,1609,2089,2161,3049,3121,3529,4561,4729,4969,5281,6481,
%T 6961,7129,7369,7681,8089,8161,9049,11689,12241,12721,12889,13441,
%U 13921,14401,16249,17449,17929,19441,19609,19681,20161,20641,20809,21121,21841,23041
%N Prime numbers congruent to 1 or 169 modulo 240 representable neither by x^2 + 150*y^2 nor by x^2 + 960*y^2.
%C Brink showed that prime numbers congruent to 1 or 169 modulo 240 are representable by both or neither of the quadratic forms x^2 + 150*y^2 and x^2 + 960*y^2. A325087 corresponds to those representable by both, and this sequence corresponds to those representable by neither.
%H David Brink, <a href="https://doi.org/10.1016/j.jnt.2008.04.007">Five peculiar theorems on simultaneous representation of primes by quadratic forms</a>, Journal of Number Theory 129(2) (2009), 464-468, doi:10.1016/j.jnt.2008.04.007, MR 2473893.
%H Rémy Sigrist, <a href="/A325088/a325088.gp.txt">PARI program for A325088</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Kaplansky%27s_theorem_on_quadratic_forms">Kaplansky's theorem on quadratic forms</a>
%e Regarding 241:
%e - 241 is a prime number,
%e - 241 = 1*240 + 1,
%e - 241 is neither representable by x^2 + 150*y^2 nor by x^2 + 960*y^2,
%e - hence 241 belongs to this sequence.
%o (PARI) See Links section.
%Y See A325067 for similar results.
%Y Cf. A325087.
%K nonn
%O 1,1
%A _Rémy Sigrist_, Mar 28 2019