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%I #21 May 19 2019 17:23:59
%S 5,8,14,26,50,98,194,386,770,1538,3074,6146,12290,24578,49154,98306,
%T 196610,393218,786434,1572866,3145730,6291458,12582914,25165826,
%U 50331650,100663298,201326594,402653186,805306370,1610612738,3221225474
%N a(n) = 3*2^n + 2.
%H Vincenzo Librandi, <a href="/A164094/b164094.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 (3,-2).
%F a(n) = A007283(n) + 2 = 3*a(n-1) - 2*a(n-2).
%F G.f.: (5-7*x)/((2*x-1)*(x-1)).
%t #+2&/@(3 2^Range[0,30]) (* _Harvey P. Dale_, Jan 23 2011 *)
%o (PARI) a(n)= 3<<n+2 \\ _Charles R Greathouse IV_, Jan 11 2012
%Y Cf. A007283.
%K nonn,easy
%O 0,1
%A _Vincenzo Librandi_, Aug 10 2009
%E Offset corrected by _R. J. Mathar_, Aug 21 2009