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(MAGMAMagma) [(4*9^n+(-1)^n)/5: n in [0..25]]; // Vincenzo Librandi, Jun 29 2011
<a href="/index/Rec#order_02">Index to sequences with entries for linear recurrences with constant coefficients</a>, signature (8,9).
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a(n) = (4*9^n + (-1)^n)/5.
E.g.f.: (4*exp(9*x) + exp(-x))/5.
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a(n) = (4*9^n+(-1)^n)/5.
<a href="/index/ReaRec#recLCCorder_02">Index to sequences with linear recurrences with constant coefficients</a>, signature (8,9).
a(n)=(4*9^n+(-1)^n)/5 G.f. (1-x)/((1-9x)(1+x)) E.g.f. (4exp(9x)+exp(-x))/5
G.f.: (1-x)/((1-*9x)(1+x)).
E.g.f.: (4*exp(9*x)+exp(-x))/5.
(MAGMA) [(4*9^n+(-1)^n)/5: n in [0..25]]; // _Vincenzo Librandi, _, Jun 29 2011
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(PARI) a(n)=4*9^n\/5 \\ _Charles R Greathouse IV, _, Jun 29 2011
_Paul Barry (pbarry(AT)wit.ie), _, Apr 24 2003