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%I #23 Jun 09 2023 07:49:01
%S 1,4,17,54,145,368,945,2530,7073,20412,60049,178478,533169,1596520,
%T 4785713,14352282,43050817,129145076,387426321,1162268326,3486792401,
%U 10460362464,31381070257,94143190994,282429550305,847288625068
%N a(n) = 3^n + n^3.
%C In this sequence if we do a forward difference, then the 4th forward difference when considered as a sequence will be a geometric progression with common ratio 3. - Gopalakrishnan (gopala498(AT)yahoo.co.in), May 26 2010
%H Vincenzo Librandi, <a href="/A001585/b001585.txt">Table of n, a(n) for n = 0..1000</a>
%H R. K. Hoeflin, <a href="http://www.eskimo.com/~miyaguch/titan.html">Titan Test</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (7, -18, 22, -13, 3).
%F G.f.: (-1+2*x^4+15*x^3-7*x^2+3*x)/((3*x-1)*(x-1)^4). - Maksym Voznyy (voznyy(AT)mail.ru), Jul 27 2009
%p seq(seq(k^n+n^k, k=3..3), n=0..23); # _Zerinvary Lajos_, Jun 29 2007
%t Table[3^n+n^3,{n,0,3*4!}] (* _Vladimir Joseph Stephan Orlovsky_, May 07 2010 *)
%o (Magma) [3^n+n^3: n in [0..30]]; // _Vincenzo Librandi_, Oct 27 2011
%Y Cf. A001580.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_
%E More terms from _Vladimir Joseph Stephan Orlovsky_, May 07 2010