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%I #12 Jan 12 2019 02:31:40
%S 65,85,185,265,365,481,485,493,533,565,629,685,697,785,865,949,965,
%T 985,1037,1073,1157,1165,1189,1241,1261,1285,1385,1417,1465,1565,1585,
%U 1649,1685,1765,1769,1781,1853,1865,1921,1937,1985,2117,2165,2173
%N Numbers of the form p_1*p_2*p_3*...*p_r where r is 2 or an odd number > 2, and the p_i are distinct primes congruent to 1 mod 4 such that Legendre(p_i/p_j) = -1 for all i != j.
%C If k is a term, the Pell equation x^2 - k*y^2 = -1 has a solution [Dirichlet, Newman (1977)]. This is only a sufficient condition, there are many other solutions, see A031396.
%H Chai Wah Wu, <a href="/A323272/b323272.txt">Table of n, a(n) for n = 1..10000</a>
%H Morris Newman, <a href="https://www.jstor.org/stable/2319968">A note on an equation related to the Pell equation</a>, The American Mathematical Monthly 84.5 (1977): 365-366.
%Y Cf. A002144, A031396. Includes the union of A322781 and A323271.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Jan 11 2019
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