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%I #30 Dec 11 2023 08:37:54
%S 1,2,7,32,157,782,3907,19532,97657,488282,2441407,12207032,61035157,
%T 305175782,1525878907,7629394532,38146972657,190734863282,
%U 953674316407,4768371582032,23841857910157,119209289550782,596046447753907
%N a(n) = (5^n + 3)/4.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (6,-5).
%F a(n) = A047848(2,n).
%F From _Philippe Deléham_, Oct 06 2009: (Start)
%F a(n) = 6*a(n-1) - 5*a(n-2) for n > 1.
%F G.f.: (1-4*x)/((1-x)*(1-5*x)). (End)
%F a(n) = 5*a(n-1) - 3 (with a(0)=1). - _Vincenzo Librandi_, Aug 06 2010
%F From _Elmo R. Oliveira_, Dec 10 2023: (Start)
%F a(n) = A132079(n)/2.
%F E.g.f.: (1/4)*(exp(5*x) + 3*exp(x)). (End)
%o (PARI) a(n)=(5^n+3)/4 \\ _Charles R Greathouse IV_, Oct 07 2015
%Y Cf. A047848, A132079.
%K nonn,easy
%O 0,2
%A _Clark Kimberling_
%E Better description from _Michael Somos_