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A157803
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8984250n - 8464830.
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3
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519420, 9503670, 18487920, 27472170, 36456420, 45440670, 54424920, 63409170, 72393420, 81377670, 90361920, 99346170, 108330420, 117314670, 126298920, 135283170, 144267420, 153251670, 162235920, 171220170, 180204420, 189188670
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The identity (1482401250*n^2-2793393900*n+1315947601)^2-(27225*n^2-51302*n+24168)*(8984250*n-8464830)^2=1 can be written as A157804(n)^2-A157802(n)*a(n)^2=1.
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..10000
Vincenzo Librandi, X^2-AY^2=1
Index to sequences with linear recurrences with constant coefficients, signature (2,-1).
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FORMULA
| Contribution from From Harvey P. Dale, Nov 01 2011: (Start)
a(1)=519420, a(2)=9503670, a(n)=2*a(n-1)-a(n-2).
G.f.: 330*x*(25651*x+1574)/(x-1)^2. (End)
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MATHEMATICA
| 8984250Range[30]-8464830 (* or *) LinearRecurrence[{2, -1}, {519420, 9503670}, 30] (* From Harvey P. Dale, Nov 01 2011 *)
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PROG
| (MAGMA) I:=[519420, 9503670]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..40]];
(PARI) a(n) = 8984250*n - 8464830.
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CROSSREFS
| Cf. A157802, A157804.
Sequence in context: A087096 A072959 A048527 * A186180 A186172 A186171
Adjacent sequences: A157800 A157801 A157802 * A157804 A157805 A157806
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KEYWORD
| nonn,easy
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 07 2009
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