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Value of x corresponding to the minimal solution of the Pell equation x^2+d*y^2, as d runs through the squarefree numbers.
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%I #6 Mar 30 2012 16:46:54

%S 1,2,1,5,8,3,10,3,15,4,4,170,5,197,24,5,5,11,1520,23,35,6,6,37,25,32,

%T 13,3482,24335,48,50,7,89,151,99,530,39,63,8,65,48842,25,251,3480,

%U 1068,43,9,53,80,9,82,9

%N Value of x corresponding to the minimal solution of the Pell equation x^2+d*y^2, as d runs through the squarefree numbers.

%D M. Pohst and H. Zassenhaus, Algorithmic Algebraic Number Theory, Cambridge Univ. Press, 1989, p. 432.

%H A. Jasinski, <a href="/A023677/b023677.txt">Table of n, a(n) for n=1..10000</a>

%t aa = {}; bb = {}; w = 0; n = 2; While[w < 100, If[SquareFreeQ[n], w = w + 1; kk = Exp[NumberFieldRegulator[Sqrt[n]]]; If[kk[[1]] == 1/2, kk = Expand[2 kk]]; AppendTo[aa, kk[[1]]]; AppendTo[bb, kk[[2]]/Sqrt[n]]]; n++ ]; aa (*Artur Jasinski*)

%Y For y values see A023678.

%K nonn

%O 1,2

%A _N. J. A. Sloane_.

%E Better definition from Artur Jasinski, Oct 23 2010