%I #42 Jul 19 2024 19:06:08
%S 1,27,729,19683,531441,14348907,387420489,10460353203,282429536481,
%T 7625597484987,205891132094649,5559060566555523,150094635296999121,
%U 4052555153018976267,109418989131512359209,2954312706550833698643
%N Powers of 27.
%C Same as Pisot sequences E(1, 27), L(1, 27), P(1, 27), T(1, 27). Essentially same as Pisot sequences E(27, 729), L(27, 729), P(27, 729), T(27, 729). See A008776 for definitions of Pisot sequences.
%C The compositions of n in which each natural number is colored by one of p different colors are called p-colored compositions of n. For n >= 1, a(n) equals the number of 27-colored compositions of n such that no adjacent parts have the same color. - _Milan Janjic_, Nov 17 2011
%H T. D. Noe, <a href="/A009971/b009971.txt">Table of n, a(n) for n = 0..100</a>
%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>
%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (27).
%F G.f.: 1/(1-27*x). - _Philippe Deléham_, Nov 24 2008
%F a(n) = 27^n; a(n) = 27*a(n-1), n > 0; a(0)=1. - _Vincenzo Librandi_, Nov 21 2010
%t 27^Range[0, 20] (* _Paolo Xausa_, Jul 19 2024 *)
%o (Sage) [lucas_number1(n,27,0) for n in range(1, 17)] # _Zerinvary Lajos_, Apr 29 2009
%o (Magma) [27^n: n in [0..100]] // _Vincenzo Librandi_, Nov 21 2010
%o (PARI) a(n)=27^n \\ _Charles R Greathouse IV_, Sep 24 2015
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_