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%I #20 Aug 27 2017 18:37:18
%S 2,12,14,26,40,66,106,172,278,450,728,1178,1906,3084,4990,8074,13064,
%T 21138,34202,55340,89542,144882,234424,379306,613730,993036,1606766,
%U 2599802,4206568,6806370,11012938
%N Fibonacci sequence beginning 2, 12.
%H G. C. Greubel, <a href="/A022368/b022368.txt">Table of n, a(n) for n = 0..1000</a>
%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1,1).
%F G.f.: 2*(1+5*x)/(1-x-x^2). - _Philippe Deléham_, Nov 19 2008
%F a(n) = 2*A022096(n). - _R. J. Mathar_, Sep 27 2014
%F a(n) = 2*(Fibonacci(n+2) + 4*Fibonacci(n)). - _G. C. Greubel_, Aug 27 2017
%t a={};b=2;c=12;AppendTo[a, b];AppendTo[a, c];Do[b=b+c;AppendTo[a, b];c=b+c;AppendTo[a, c], {n, 4!}];a (* _Vladimir Joseph Stephan Orlovsky_, Sep 18 2008 *)
%t Table[2*(Fibonacci[n + 2] + 4*Fibonacci[n]), {n,0,50}] (* or *) LinearRecurrence[{1,1}, {2,12}, 50] (* _G. C. Greubel_, Aug 27 2017 *)
%o (PARI) for(n=0,50, print1(2*(fibonacci(n+2) + 4*fibonacci(n)), ", ")) \\ _G. C. Greubel_, Aug 27 2017
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_
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