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A084431 Expansion of (1 + 6*x + 5*x^2)/((1-2*x)*(1+2*x)). 2

%I

%S 1,6,9,24,36,96,144,384,576,1536,2304,6144,9216,24576,36864,98304,

%T 147456,393216,589824,1572864,2359296,6291456,9437184,25165824,

%U 37748736,100663296,150994944,402653184,603979776,1610612736,2415919104

%N Expansion of (1 + 6*x + 5*x^2)/((1-2*x)*(1+2*x)).

%C Binomial transform is A085287.

%H Vincenzo Librandi, <a href="/A084431/b084431.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,4)

%F a(n) = (-10*0^n - 3*(-2)^n + 21*2^n)/8.

%F a(n) = 4*a(n-2), n > 1. - _Harvey P. Dale_, Nov 05 2011

%t CoefficientList[Series[(1+6x+5x^2)/((1-2x)(1+2x)),{x,0,30}],x] (* or *) Join[{1},Flatten[NestList[4#&,{6,9},15]]] (* _Harvey P. Dale_, Nov 05 2011 *)

%o (MAGMA) [(-10*0^n-3*(-2)^n+21*2^n)/8: n in [0..30]]; // _Vincenzo Librandi_, Nov 16 2011

%Y Bisections are A002023 and A002063.

%K nonn,easy

%O 0,2

%A _Paul Barry_, Jun 26 2003

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Last modified May 7 20:36 EDT 2021. Contains 343652 sequences. (Running on oeis4.)