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%I #15 Sep 18 2022 19:29:56
%S 1,8,43,197,841,3473,14113,56897,228481,915713,3666433,14672897,
%T 58705921,234852353,939466753,3757981697,15032156161,60129083393,
%U 240517251073,962070839297,3848287027201,15393155448833,61572636475393
%N a(n) = 6*a(n-1)-8*a(n-2)+3 for n > 1; a(0) = 1, a(1) = 8.
%H Vincenzo Librandi, <a href="/A171479/b171479.txt">Table of n, a(n) for n = 0..500</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (7,-14,8)
%F a(n) = (2-7*2^n+7*4^n)/2.
%F G.f.: (1+x+x^2)/((1-x)*(1-2*x)*(1-4*x)).
%p A171479:=n->(2-7*2^n+7*4^n)/2: seq(A171479(n), n=0..30); # _Wesley Ivan Hurt_, Apr 28 2017
%t LinearRecurrence[{7,-14,8},{1,8,43},30] (* _Harvey P. Dale_, Sep 18 2022 *)
%o (PARI) {m=23; v=concat([1, 8], vector(m-2)); for(n=3, m, v[n]=6*v[n-1]-8*v[n-2]+3); v}
%o (Magma) [(2-7*2^n+7*4^n)/2: n in [0..30]]; // _Vincenzo Librandi_, Jul 18 2011
%Y Cf. A171472, A171473, A171478.
%K nonn,easy
%O 0,2
%A _Klaus Brockhaus_, Dec 09 2009