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10, 16, 26, 40, 58, 80, 106, 136, 170, 208, 250, 296, 346, 400, 458, 520, 586, 656, 730, 808, 890, 976, 1066, 1160, 1258, 1360, 1466, 1576, 1690, 1808, 1930, 2056, 2186, 2320, 2458, 2600, 2746, 2896, 3050, 3208, 3370, 3536, 3706, 3880, 4058
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OFFSET
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1,1
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COMMENTS
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The identity (n^3+4*n)^2+(2*n^2+8)^2=(n^2+4)^3 can be written as A155965(n)^2+a(n)^2=A087475(n)^3.
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LINKS
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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
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G.f.: x*(10-14*x+8*x^2)/(1-x)^3.
a(n) = 3*a(n-1) -3*a(n-2) +a(n-3).
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MATHEMATICA
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LinearRecurrence[{3, -3, 1}, {10, 16, 26}, 50] (* Vincenzo Librandi, Feb 22 2012
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PROG
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(PARI) a(n)=2*n^2+8 \\ Charles R Greathouse IV, Jan 11 2012
(MAGMA) I:=[10, 16, 26]; [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, Feb 22 2012
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CROSSREFS
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Sequence in context: A152138 A109100 A155151 * A104788 A036063 A080360
Adjacent sequences: A155963 A155964 A155965 * A155967 A155968 A155969
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KEYWORD
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nonn,easy,changed
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AUTHOR
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Vincenzo Librandi, Jan 31 2009
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STATUS
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approved
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