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1122, 2453, 3784, 5115, 6446, 7777, 9108, 10439, 11770, 13101, 14432, 15763, 17094, 18425, 19756, 21087, 22418, 23749, 25080, 26411, 27742, 29073, 30404, 31735, 33066, 34397, 35728, 37059, 38390, 39721, 41052, 42383, 43714, 45045, 46376
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The identity (14641*n^2-4598*n+362)^2-(121*n^2-38*n+3)*(1331*n-209)^2=1 can be written as A157445(n)^2-A157443(n)*a(n)^2=1. - Vincenzo Librandi, Jan 26 2012
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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
| a(n) = 2*a(n-1)-a(n-2). - Vincenzo Librandi, Jan 26 2012
G.f.: x*(209*x+1122)/(x-1)^2. - Vincenzo Librandi, Jan 26 2012
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MATHEMATICA
| LinearRecurrence[{2, -1}, {1122, 2453}, 40] (* Vincenzo Librandi, Jan 26 2012 *)
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PROG
| (MAGMA) I:=[1122, 2453]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]]; // Vincenzo Librandi, Jan 26 2012
(PARI) for(n=1, 22, print1(1331*n - 209", ")); \\ Vincenzo Librandi, Jan 26 2012
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CROSSREFS
| Cf. A157443, A157445.
Sequence in context: A122052 A207014 A203189 * A158729 A035859 A105310
Adjacent sequences: A157441 A157442 A157443 * A157445 A157446 A157447
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KEYWORD
| nonn,easy
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 01 2009
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