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A015581
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a(n) = 9*a(n-1) + 5*a(n-2).
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3
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0, 1, 9, 86, 819, 7801, 74304, 707741, 6741189, 64209406, 611590599, 5825362421, 55486214784, 528502745161, 5033955780369, 47948115749126, 456702820643979, 4350065964541441, 41434107784092864, 394657299879542981, 3759086237836351149, 35805062639924875246
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OFFSET
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0,3
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COMMENTS
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A linear 2nd-order recurrence.
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LINKS
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FORMULA
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MATHEMATICA
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PROG
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(Sage) [lucas_number1(n, 9, -5) for n in range(0, 19)] # Zerinvary Lajos, Apr 26 2009
(Magma) [n le 2 select n-1 else 9*Self(n-1) + 5*Self(n-2): n in [1..30]]; // Vincenzo Librandi, Nov 15 2012
(PARI) x='x+O('x^30); concat([0], Vec(x/(1-9*x-5*x^2))) \\ G. C. Greubel, Jan 06 2018
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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