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Period 2: repeat (5,9).
4

%I #24 Dec 14 2023 06:05:39

%S 5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,

%T 5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,5,9,

%U 5,9,5,9,5,9,5,9,5,9,5,9,5

%N Period 2: repeat (5,9).

%C Continued fraction expansion of A176324. - _R. J. Mathar_, Mar 08 2012

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0,1).

%F a(n) = -2*(-1)^n + 7. - _Paolo P. Lava_, Oct 20 2006

%F a(n) = a(n-2) for n > 1; a(0) = 5, a(1) = 9. G.f.: (5+9*x)/((1-x)*(1+x)). - _Vincenzo Librandi_, Aug 01 2010

%t Table[5 + 4 Mod[n, 2], {n, 0, 50}] (* _Jinyuan Wang_, Feb 26 2020 *)

%o (PARI) a(n)=n%2*4+5 \\ _Charles R Greathouse IV_, Jul 13 2016

%K nonn,easy

%O 0,1

%A _N. J. A. Sloane_