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a(n) = A371764(n, 2).
1

%I #20 May 25 2024 15:32:02

%S 1,14,86,374,1382,4694,15206,47894,148262,453974,1380326,4177814,

%T 12607142,37968854,114201446,343194134,1030762022,3094645334,

%U 9288654566,27875400854,83645076902,250972979414,752994435686,2259134301974

%N a(n) = A371764(n, 2).

%H Paolo Xausa, <a href="/A372148/b372148.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (6,-11,6).

%F a(n) = 2*(4*3^n - 9*2^n + 7) - [n = 1]. - _Hugo Pfoertner_, Apr 20 2024

%F G.f.: x*(1 + 8*x + 13*x^2 + 6*x^3)/((1 - x)*(1 - 2*x)*(1 - 3*x)). - _Stefano Spezia_, Apr 21 2024

%p a := n -> 2*(4*3^n - 9*2^n + 7) - `if`(n=1, 1, 0);

%p seq(a(n), n = 1..24); # _Peter Luschny_, Apr 20 2024

%t A372148[n_] := 2*(4*3^n - 9*2^n + 7) - Boole[n == 1]; Array[A372148,50] (* or *)

%t LinearRecurrence[{6, -11, 6}, {1, 14, 86, 374}, 50] (* _Paolo Xausa_, May 25 2024 *)

%Y Cf. A371764.

%K nonn,easy

%O 1,2

%A _Detlef Meya_, Apr 20 2024