%I A158401
%S A158401 839,3360,7563,13448,21015,30264,41195,53808,68103,84080,101739,121080,
%T A158401 142103,164808,189195,215264,243015,272448,303563,336360,370839,407000,
%U A158401 444843,484368,525575,568464,613035,659288,707223,756840,808139,861120
%N A158401 a(n)=841*n^2-2*n (n>0)
%C A158401 If A=[A158401] 841*n.^2-2*n (n>0, 839, 3360, 7563,.,); Y=[A010868] 29 
               (29, 29, 29, ,.,); X=[A158402] 841*n-1 (n>0, 840, 1681, 2522, .,), 
               we have, for all terms, Pell's equation X^2-A*Y^2=1. Example: 840^2-839*29^2=1; 
               1681^2-3360*29^2=1; 2522^2-7563*29^2=1.
%H A158401 Edward Everett Withford, <a href="http://quod.lib.umich.edu/cgi/t/text/
               text-idx?c=umhistmath;cc=umhistmath;idno=abv2773.0001.001;view=toc">
               Pell Equation</a>
%H A158401 Vincenzo Librandi, <a href="http://mathforum.org/kb/message.jspa?messageID=5785989&tstart=0">
               X^2-AY^2=1</a>
%H A158401 Wolfram MathWorld, <a href="http://mathworld.wolfram.com/PellEquation.html">
               Pell Equation</a>
%F A158401 a(n)=841*n^2-2*n (n>0)
%e A158401 For n=1, a(1)=839; n=2, a(2)=3360; n=3, a(3)=7563
%Y A158401 Cf. A010868, A158402
%Y A158401 Sequence in context: A167603 A118380 A135639 this_sequence A156937 A135640 
               A095119
%Y A158401 Adjacent sequences: A158398 A158399 A158400 this_sequence A158402 A158403 
               A158404
%K A158401 nonn
%O A158401 1,1
%A A158401 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 18 2009