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a(n) = 11*2^n.
13

%I #46 Aug 16 2024 19:03:34

%S 11,22,44,88,176,352,704,1408,2816,5632,11264,22528,45056,90112,

%T 180224,360448,720896,1441792,2883584,5767168,11534336,23068672,

%U 46137344,92274688,184549376,369098752,738197504,1476395008,2952790016,5905580032,11811160064

%N a(n) = 11*2^n.

%C The first differences are the sequence itself. - _Alexandre Wajnberg_ & _Eric Angelini_, Sep 07 2005

%C 11 times powers of 2. - _Omar E. Pol_, Dec 16 2008

%C A144472 = -1,2,9,13,31,57,.... a(n) = A144472(n+1)+A144472(n+2). Also a(n) = A144472(n+3)-A144472(n+1). A144472(n+1) is a Jacobsthal sequence from 2 and 9: A144472(n+3) = A144472(n+2)+2*A144472(n+1). Note a(n) mod 9 = period 6: repeat 2,4,8,7,5,1 = A153130(n+1). - _Paul Curtz_, Jan 06 2009

%H Vincenzo Librandi, <a href="/A005015/b005015.txt">Table of n, a(n) for n = 0..1000</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 (2).

%F G.f.: 11/(1-2*x).

%F a(n) = 2*a(n-1), n>0; a(0)=11. - _Philippe Deléham_, Nov 23 2008

%F a(n) = A000079(n)*11. - _Omar E. Pol_, Dec 16 2008

%F E.g.f.: 11*exp(2*x). - _Elmo R. Oliveira_, Aug 16 2024

%t 11*2^Range[0, 60] (* _Vladimir Joseph Stephan Orlovsky_, Jun 09 2011 *)

%t NestList[2#&,11,30] (* _Harvey P. Dale_, Jun 11 2021 *)

%o (Magma) [11*2^n: n in [0..40]]; // _Vincenzo Librandi_, Aug 14 2011

%o (PARI) a(n)=11<<n \\ _Charles R Greathouse IV_, Oct 07 2015

%Y Row sums of (10, 1)-Pascal triangle A093645.

%Y Cf. A000079, A144472, A153130.

%K nonn,easy

%O 0,1

%A _N. J. A. Sloane_