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A157859
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103680000n^2 - 28800n + 1.
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3
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103651201, 414662401, 933033601, 1658764801, 2591856001, 3732307201, 5080118401, 6635289601, 8397820801, 10367712001, 12544963201, 14929574401, 17521545601, 20320876801, 23327568001, 26541619201, 29963030401, 33591801601
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The identity (103680000*n^2-28800*n+1)^2-(3600*n^2-n)*(1728000*n-240)^2=1 can be written as a(n)^2-A157857(n)*A157858(n)^2=1 (see second comment in A157858). - Vincenzo Librandi, Jan 25 2012
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..10000
Vincenzo Librandi, X^2-AY^2=1
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FORMULA
| a(n) = 3*a(n-1) -3*a(n-2) +a(n-3). - Vincenzo Librandi, Jan 25 2012
G.f.: x*(-103651201-103708798*x-x^2)/(x-1)^3. - Vincenzo Librandi, Jan 25 2012
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MATHEMATICA
| LinearRecurrence[{3, -3, 1}, {103651201, 414662401, 933033601}, 40] (* Vincenzo Librandi, Jan 25 2012 *)
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PROG
| (MAGMA) I:=[103651201, 414662401, 933033601]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..40]]; // Vincenzo Librandi, Jan 25 2012
(PARI) for(n=1, 22, print1(103680000*n^2 - 28800*n + 1", ")); \\ Vincenzo Librandi, Jan 25 2012
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CROSSREFS
| Cf. A157857, A157858.
Sequence in context: A073643 A112717 A114679 * A157863 A035498 A018897
Adjacent sequences: A157856 A157857 A157858 * A157860 A157861 A157862
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KEYWORD
| nonn,easy
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 08 2009
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