%I A157436
%S A157436 15137,18049,21217,24641,28321,32257,36449,40897,45601,50561,55777,
%T A157436 61249,66977,72961,79201,85697,92449,99457,106721,114241,122017,130049,
%U A157436 138337,146881,155681,164737,174049,183617,193441,203521,213857,224449
%N A157436 a(n)=128*n^2+528*n+12481 (n>0)
%C A157436 If A=[A157434] 4*n.^2+79*n +390 (473,564,663,770,.,); Y=[A157435] 64*n+632
(696, 760, 824,888,..,); X=[A157433] 128*n^2+2528*n+12481 (15137,
18049,21217,24641,.,) ; , we have for all terms, Pell's equation
X^2-A*Y^2=1. Example: 15137^2-473*696^2=1; 18049^2-564*760^2=1; 21217^2-663*824^2=1.
%H A157436 Vincenzo Librandi, <a href="http://mathforum.org/kb/message.jspa?messageID=5773147&tstart=0">
X^2-AY^2=1</a>
%F A157436 a(n)=128*n^2+528*n+12481 (n>0)
%e A157436 For n=1, a(1)=15137; n=2, a(2)=18049; n=3, a(3)=21217
%Y A157436 Cf. A157434, A157435
%Y A157436 Sequence in context: A004935 A004955 A004975 this_sequence A105924 A115924
A064982
%Y A157436 Adjacent sequences: A157433 A157434 A157435 this_sequence A157437 A157438
A157439
%K A157436 nonn
%O A157436 1,1
%A A157436 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 01 2009
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