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650, 2525, 5650, 10025, 15650, 22525, 30650, 40025, 50650, 62525, 75650, 90025, 105650, 122525, 140650, 160025, 180650, 202525, 225650, 250025, 275650, 302525, 330650, 360025, 390650, 422525, 455650, 490025, 525650, 562525, 600650, 640025
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The identity (50*n^2+1)^2-(625*n^2+25)*(2*n)^2 = 1 can be written as A157916(n)^2-a(n)*A005843(n)^2 = 1. - Vincenzo Librandi, Feb 10 2012
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..10000
Index to sequences with linear recurrences with constant coefficients, signature (3,-3,1).
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FORMULA
| G.f: x*(650+575*x+25*x^2)/(1-x)^3. - Vincenzo Librandi, Feb 10 2012
a(n)=3*a(n-1)-3*a(n-2)+a(n-3). - Vincenzo Librandi, Feb 10 2012
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MATHEMATICA
| 625Range[40]^2+25 (* From Harvey P. Dale, Apr 05 2011 *)
LinearRecurrence[{3, -3, 1}, {650, 2525, 5650}, 40] (* Vincenzo Librandi, Feb 10 2012 *)
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PROG
| (MAGMA) I:=[650, 2525, 5650]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+Self(n-3): n in [1..50]]; // Vincenzo Librandi, Feb 10 2012
(PARI) for(n=1, 40, print1(625*n^2 + 25", ")); \\ Vincenzo Librandi, Feb 10 2012
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CROSSREFS
| Cf. A005843, A157916.
Sequence in context: A154358 A185666 A114047 * A158639 A162025 A035851
Adjacent sequences: A157912 A157913 A157914 * A157916 A157917 A157918
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KEYWORD
| nonn,easy,changed
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 09 2009
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