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%I #46 Sep 08 2022 08:45:20
%S 15,30,60,120,240,480,960,1920,3840,7680,15360,30720,61440,122880,
%T 245760,491520,983040,1966080,3932160,7864320,15728640,31457280,
%U 62914560,125829120,251658240,503316480,1006632960,2013265920,4026531840,8053063680,16106127360
%N a(n) = 15*2^n.
%C The first differences are the sequence itself. Doubling the terms gives the same sequence (beginning one step further).
%H Vincenzo Librandi, <a href="/A110286/b110286.txt">Table of n, a(n) for n = 0..235</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.: 15/(1-2x). - _Philippe Deléham_, Nov 23 2008
%F a(n) = A000079(n)*15 = A007283(n)*5 = A020714(n)*3. - _Omar E. Pol_, Dec 17 2008
%F a(n) = A173787(n+4,n). - _Reinhard Zumkeller_, Feb 28 2010
%F Subsequence of A051916. - _Reinhard Zumkeller_, Mar 20 2010
%F a(n) = 2*a(n-1) (with a(0)=15). - _Vincenzo Librandi_, Dec 26 2010
%F E.g.f.: 15*exp(2*x). - _Stefano Spezia_, May 15 2021
%t 15*2^Range[0, 60] (* _Vladimir Joseph Stephan Orlovsky_, Jun 09 2011 *)
%t NestList[2#&,15,30] (* _Harvey P. Dale_, Oct 19 2014 *)
%o (Magma) [15*2^n: n in [0..40]]; // _Vincenzo Librandi_, Apr 28 2011
%o (PARI) a(n)=15<<n \\ _Charles R Greathouse IV_, Oct 07 2015
%Y Cf. A007283, A020714, A005009, A005010, A005015, A005029.
%Y Cf. A000079, A051916, A173787.
%K easy,nonn
%O 0,1
%A _Alexandre Wajnberg_, Sep 07 2005
%E Edited by _Omar E. Pol_, Dec 16 2008
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