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Values of x such that x^2 + y^2 = 29^n with x and y coprime and 0 < x < y.
8

%I #20 Mar 02 2014 08:15:07

%S 2,20,65,41,1475,15939,60422,68880,1063438,12631900,55535695,86719879,

%T 743336365,9948240141,50564635018,96971881440,496655601122,

%U 7778740572980,45669244934945,101577438080201,308633722311395,6032082927439779,40960925870541542

%N Values of x such that x^2 + y^2 = 29^n with x and y coprime and 0 < x < y.

%C The corresponding y-values are in A230645.

%H Vincenzo Librandi, <a href="/A230644/b230644.txt">Table of n, a(n) for n = 1..200</a>

%e a(3)=65 because 65^2+142^2=24389=29^3.

%t Table[Select[PowersRepresentations[29^n, 2, 2], CoprimeQ@@#&][[1, 1]], {n, 1, 40}] (* _Vincenzo Librandi_, Mar 02 2014 *)

%Y Cf. A009973, A188948, A230622, A230645.

%K nonn

%O 1,1

%A _Colin Barker_, Oct 26 2013

%E Incorrect formula deleted by _Colin Barker_, Jan 08 2014