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a(0)=22; if n odd, a(n) = a(n-1)/2, otherwise a(n) = 4*a(n-1).
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%I #20 Mar 12 2024 22:51:37

%S 22,11,44,22,88,44,176,88,352,176,704,352,1408,704,2816,1408,5632,

%T 2816,11264,5632,22528,11264,45056,22528,90112,45056,180224,90112,

%U 360448,180224,720896,360448,1441792,720896

%N a(0)=22; if n odd, a(n) = a(n-1)/2, otherwise a(n) = 4*a(n-1).

%C A108213 is a subsequence of this sequence and is also twice this sequence.

%H Harvey P. Dale, <a href="/A108732/b108732.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0,2)

%F a(2n+1) = a(2n-2).

%F Recurrence: a(n) = 2a(n-2), a(0)=22, a(1)=11. G.f.: (22x+44)/(1-2x^2). - _Ralf Stephan_, Jul 16 2013

%F a(n) = 11 * 2^A028242(n). - _Franklin T. Adams-Watters_, Mar 29 2006

%t nxt[{n_,a_}]:={n+1,If[EvenQ[n],a/2,4a]}; NestList[nxt,{0,22},40][[All,2]] (* or *) LinearRecurrence[{0,2},{22,11},40] (* _Harvey P. Dale_, Jul 22 2021 *)

%Y Cf. A005015, A108213.

%K easy,nonn

%O 0,1

%A _Alexandre Wajnberg_ & Guadalupe Garcia, Jun 22 2005