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%I #16 Feb 26 2015 08:26:46
%S 2,3,5,4,8,5,7,11,8,7,12,14,8,11,13,10,12,10,16,18,15,11,17,14,19,21,
%T 20,14,17,26,21,14,18,23,16,15,19,24,18,26,32,23,20,25,19,22,17,29,35,
%U 18,28,25,32,21,34,19,29,23,26,31,22,33,28,37,39,41,24
%N One half of the fundamental positive solution y = y2(n) of the second class of the Pell equation x^2 - 2*y^2 = -A007522(n), n>=1 (primes congruent to 7 mod 8).
%C The corresponding fundamental solution x2(n) of this second class of positive solutions is given in A255233(n).
%C See the comments and the Nagell reference in A254938.
%F A255233(n)^2 - 2*(2*a(n))^2 = -A007522(n) gives the second smallest positive (proper) solution of this (generalized) Pell equation.
%F a(n) = -(A254938(n) - 3*A255232(n)), n >= 1.
%e n = 2: 7^2 - 2*(2*3)^2 = 49 - 72 = -23 = - A007522(2).
%e a(3) = -(1 - 3*2) = 5.
%e See also A255233.
%Y Cf. A007522, A255233, A254938, A255232, A254937.
%K nonn,look,easy
%O 1,1
%A _Wolfdieter Lang_, Feb 19 2015
%E More terms from _Colin Barker_, Feb 24 2015
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