Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #16 Jan 14 2018 03:25:44
%S 2,15,117,945,7857,66825,578097,5062905,44726337,397498185,3547250577,
%T 31743856665,284606318817,2554926522345,22955156619057,
%U 206361317079225,1855841298759297,16694108359111305,150196195253667537
%N a(n) = 6^n + 9^n.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (15,-54).
%F From _Mohammad K. Azarian_, Jan 11 2009: (Start)
%F G.f.: 1/(1-6*x) + 1/(1-9*x).
%F E.g.f.: e^(6*x) + e^(9*x). (End)
%F a(n) = 15*a(n-1) - 54*a(n-2) with a(0)=2, a(1)=15. - _Vincenzo Librandi_, Jul 21 2010
%t Table[6^n + 9^n, {n, 0, 20}]
%Y Cf. A000051, A034472, A052539, A034474, A062394, A034491, A062395, A062396, A007689, A063376, A063481, A074600..A074624.
%K easy,nonn
%O 0,1
%A _Robert G. Wilson v_, Aug 26 2002