%I #18 Jan 25 2014 16:39:17
%S 7,8,4,3,8,4,4,8,20,4,3,4,4,8,20,4,8,4,8,7,4,3,
%T 8,4,4,4,3,8,4,4,3,8,4,8,4,3,4,8,20,4,8,4,7,4,
%U 4,3,8,3,8,4,4,7,4,8,4,20,4,3,4,4,8,4,8,11,4,4,8,4,8,4,4,7,3,4,8
%N Choose smallest m>0 such that the nth rational prime p splits in the imaginary quadratic extension field K = Q(sqrt(m)); a(n) = discriminant(K).
%C a(n) = discriminant of extension field defined in A220862.
%D David A. Cox, "Primes of the Form x^2 + n y^2", Wiley, 1989, Cor. 5.17, p. 105.
%F Let i = A220862(n). Then a(n) = i if i == 1 (mod 4), otherwise 4i.
%Y Cf. A088192, A220861, A220862.
%K sign
%O 1,1
%A _N. J. A. Sloane_, Dec 26 2012
