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Numbers of form x^2+5y^2 (x>=0,y>=0) with repetition.
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%I #9 Jan 25 2014 16:39:16

%S 0,1,4,5,6,9,9,14,16,20,21,21,24,25,29,30,36,36,41,45,45,46,49,49,54,

%T 54,56,61,64,69,69,70,80,81,81,81,84,84,86,89,94,96,100,101,105,105,

%U 109,116,120,121,125,126,126,126,129,129,134,141,141,144,144,145,149,150

%N Numbers of form x^2+5y^2 (x>=0,y>=0) with repetition.

%C Primes in the sequence occur only once.

%D David A. Cox, "Primes of the Form x^2 + n y^2", Wiley, 1989.

%e 0 = 0^2+5*0^2,

%e 9 = 2^2+5*1^2 = 3^2+5*0^2,

%e 81 = 1^2+5*4^2 = 6^2+5*3^2 = 9^2+5*0^2,

%e 441: {x,y}={6,9},{11,8},{14,7},{19,4},{21,0}.

%Y Cf. A033205.

%K nonn

%O 1,3

%A _Zak Seidov_, Apr 26 2008