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%I #17 Jun 30 2023 18:57:29
%S 13,55,223,895,3583,14335,57343,229375,917503,3670015,14680063,
%T 58720255,234881023,939524095,3758096383,15032385535,60129542143,
%U 240518168575,962072674303,3848290697215,15393162788863,61572651155455,246290604621823,985162418487295
%N a(n) = 14 * 4^n - 1.
%H G. C. Greubel, <a href="/A206372/b206372.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 (5, -4).
%F a(n) = 7*2^(2*n+1) - 1.
%F a(n) = (A199207(n+1) -3)/2 for n>=0.
%F From _G. C. Greubel_, Jan 05 2023: (Start)
%F a(n) = A005009(2*n+1) - 1.
%F G.f.: (13 - 10*x)/((1-x)*(1-4*x)).
%F E.g.f.: 14*exp(4*x) - exp(x). (End)
%t 7*2^(2*Range[0,50]+1)-1 (* _G. C. Greubel_, Jan 05 2023 *)
%o (Magma) [14*4^n-1 : n in [0..30]];
%o (PARI) a(n)=14*4^n - 1 \\ _Charles R Greathouse IV_, May 05 2014
%o (SageMath) [7*2^(2*n+1)-1 for n in range(51)] # _G. C. Greubel_, Jan 05 2023
%Y Cf. A005009, A199207.
%K nonn,easy
%O 0,1
%A _Brad Clardy_, Feb 07 2012
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