A102708 - OEIS

A102708

Composite numbers a(n) having a GCD with Pell_x(a(n))-1 equal to 1 (where Pell_x(n) is the x solution of the Pell-Fermat equation: x^2 - n y^2 = 1). There is no square in the sequence because the Pell-Fermat equation has no solution for them.

%I #4 Nov 02 2014 18:36:59

%S 27,51,65,85,123,125,145,171,185,187,243,265,267,291,325,339,363,365,

%T 387,411,425,445,451,459,481,485,493,531,533,565,603,627,629,685,697,

%U 699,731,771,779,785,803,843,845,865,867,901,925,949,963,965,985,1003

%N Composite numbers a(n) having a GCD with Pell_x(a(n))-1 equal to 1 (where Pell_x(n) is the x solution of the Pell-Fermat equation: x^2 - n y^2 = 1). There is no square in the sequence because the Pell-Fermat equation has no solution for them.

%K nonn

%O 0,1

%A _Thomas Baruchel_, Feb 05 2005