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%I #10 Jul 19 2015 01:43:50
%S 2,1,4,3,3,180,8,39,5,1820,273,12,320,531,7,9100,69,226153980,5967,
%T 413,267000,9,9,53000,6377352,20,22419,93,15140424455100,113296,
%U 419775,927,519712,6578829,2113761020,140634693,3726964292220,5019135,13,190060
%N Let p = n-th prime, take smallest solution (x,y) to the Pellian equation x^2 - p*y^2 = 1 with x and y >= 1; sequence gives value of y.
%H N. J. A. Sloane et al., <a href="https://oeis.org/wiki/Binary_Quadratic_Forms_and_OEIS">Binary Quadratic Forms and OEIS</a> (Index to related sequences, programs, references)
%t PellSolve[(m_Integer)?Positive] := Module[{cf, n, s}, cf = ContinuedFraction[ Sqrt[m]]; n = Length[Last[cf]]; If[OddQ[n], n = 2*n]; s = FromContinuedFraction[ ContinuedFraction[ Sqrt[m], n]]; {Numerator[s], Denominator[s]}]; Table[ PellSolve[ Prime[n]][[2]], {n, 40}] (* _Robert G. Wilson v_, Jul 22 2005 *)
%Y Values of x are in A081233. Equals A002349(p). Cf. A082393.
%K easy,nonn
%O 1,1
%A _N. J. A. Sloane_, Apr 18 2003
%E More terms (a(8) - a(40)) from _Robert G. Wilson v_, Jul 22 2005
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