login
Positive fundamental solution x0 corresponding to the even y0 = 2*A261250 of the Pell equation x^2 - D y^2 = +1.
3

%I #13 Aug 10 2022 07:57:16

%S 3,9,5,19,7,649,15,33,17,9,55,197,51,127,9801,11,23,35,73,37,25,2049,

%T 13,199,161,24335,99,649,66249,485,89,15,151,19603,31,1766319049,63,

%U 129,65,33,7775,251,17,2281249,3699,57799,351,53,163,55,285769,10405,500001,19,1151,12151,2143295,39,62809633,99,201,101,41,32080051,1351,158070671986249,21,295,127,1204353,1025,9801,649,306917

%N Positive fundamental solution x0 corresponding to the even y0 = 2*A261250 of the Pell equation x^2 - D y^2 = +1.

%C This is a proper subset of A033313 corresponding to the even members of A033317.

%C The D values coincide apparently with A007969 (Conway's rectangular numbers).

%C For a proof of this coincidence see the W. Lang link under A007969. - _Wolfdieter Lang_, Oct 04 2015

%e See A261250.

%Y Cf. A000037, A033313, A033317, A261250, A007969.

%K nonn

%O 1,1

%A _Wolfdieter Lang_, Sep 16 2015