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Minimal positive solution x of Pell equation y^2 - A077426(n)*x^2 = -4.
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%I #10 Jun 21 2013 13:58:34

%S 1,1,2,1,2,10,1,5,2,250,1,106,1138,2,25,146,1,298,2,5,17,1,97,10,

%T 253970,2,1,3034,9148450,2,746,10,157,126890,1,14341370,5,2,110671282,

%U 986,7586,1,530,130,173,2,11068353370,21685,26,694966754,1,17883410,5528222698,17,87922,2,5,41

%N Minimal positive solution x of Pell equation y^2 - A077426(n)*x^2 = -4.

%C The corresponding values y are given in A078356.

%C For the general solution of Pell equation y^2 - A077426(n)*x^2 = -4 see a comment in A078356.

%C For the conversion of the values given in Perron's table to sequences A078356 and A078357, see comments in A078356.

%D O. Perron, "Die Lehre von den Kettenbruechen, Bd.I", Teubner, 1954, 1957 (Sec. 30, Satz 3.35, p. 109 and table p. 108).

%H Vincenzo Librandi, <a href="/A078357/b078357.txt">Table of n, a(n) for n = 1..120</a>

%t $MaxExtraPrecision = 100; A077426 = Select[Range[ 600], ! IntegerQ[Sqrt[#]] && OddQ[ Length[ ContinuedFraction[(Sqrt[#] + 1)/2] // Last]] &]; a[n_] := {y, x} /. {ToRules[ Reduce[y > 0 && x > 0 && y^2 - A077426[[n]]*x^2 == -4, {y, x}, Integers] /. C[1] -> 0]} // Sort // First // Last; Table[a[n], {n, 1, 60}] (* _Jean-François Alcover_, Jun 21 2013 *)

%K nonn

%O 1,3

%A _Wolfdieter Lang_, Nov 29 2002

%E Edited and extended by _Max Alekseyev_, Mar 03 2010