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Values of x such that x^2 + y^2 = 37^n with x and y coprime and 0 < x < y.
6

%I #12 Mar 02 2014 08:15:21

%S 1,12,107,840,5646,27755,124158,462961,961686,5589325,102654282,

%T 1025046359,8502347874,64101459205,356029844147,1681548425760,

%U 7005476875681,21848430755052,2978524660427,772649642011800

%N Values of x such that x^2 + y^2 = 37^n with x and y coprime and 0 < x < y.

%C The corresponding y-values are in A230713.

%H Vincenzo Librandi, <a href="/A230712/b230712.txt">Table of n, a(n) for n = 1..200</a>

%e a(3)=107 because 107^2+198^2=50653=37^3.

%t Table[Select[PowersRepresentations[37^n, 2, 2], CoprimeQ@@#&][[1, 1]], {n, 1, 40}] (* _Vincenzo Librandi_, Mar 02 2014 *)

%Y Cf. A009981, A188948, A230622, A230644, A230710, A230713.

%K nonn

%O 1,2

%A _Colin Barker_, Oct 28 2013