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%I #15 Mar 23 2024 08:05:42
%S 5,10,17,28,47,82,149,280,539,1054,2081,4132,8231,16426,32813,65584,
%T 131123,262198,524345,1048636,2097215,4194370,8388677,16777288,
%U 33554507,67108942,134217809,268435540,536870999,1073741914,2147483741
%N a(n) = 2^n + 3*n.
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (4,-5,2).
%F a(n) = 4*a(n-1)-5*a(n-2)+2*a(n-3). G.f.: x*(5-10*x+2*x^2)/((1-x)^2*(1-2*x)). [_Colin Barker_, Sep 05 2012]
%F a(n) = A000079(n) + A008585(n). - _Michel Marcus_, Mar 23 2024
%p seq(2^n + 3*n,n=1..40);
%t Table[2^n+3n,{n,40}] (* or *) LinearRecurrence[{4,-5,2},{5,10,17},40] (* _Harvey P. Dale_, Dec 12 2013 *)
%Y Cf. A000079, A008585.
%K easy,nonn
%O 1,1
%A Robert H Rosseau (rhrosseau(AT)yahoo.com), Sep 11 2003
%E More terms from _Ray Chandler_, Sep 16 2003