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Numbers n such that 10^11 + n^2 is a square.
1

%I #18 Sep 08 2022 08:45:54

%S 3750,75000,150000,232500,241875,326625,337500,450000,585000,749250,

%T 768750,975000,1230000,1546500,1584375,1940325,1987500,2490000,

%U 3117000,3899850,3993750,4995000,6246000,7809300,7996875,9763065,9997500

%N Numbers n such that 10^11 + n^2 is a square.

%C There are 60 values of x>0 which satisfy 10^11 + x^2 = y^2. - _Bruno Berselli_, Jan 29 2013

%H Giovanni Resta, <a href="/A180974/b180974.txt">Table of n, a(n) for n = 1..60</a> (full sequence)

%t Block[{x,y}, x /. List@ToRules@Reduce[10^11 + x^2 == y^2 && y > x > 0, Integers]] (* _Giovanni Resta_, Jan 29 2013 *)

%o (Magma) [n: n in [0..10^7] | IsSquare(n^2 + 10^11)]; // _Vincenzo Librandi_, Jan 29 2013

%o (PARI) is(n)=issquare(10^11+n^2) \\ _Charles R Greathouse IV_, Jan 29 2013

%K nonn,easy,fini,full

%O 1,1

%A _Jason Earls_, Sep 30 2010