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%I #13 Sep 08 2022 08:45:30
%S 4,8,22,64,205,683,2341,8192,29128,104858,381301,1398102,5162221,
%T 19173962,71582789,268435456,1010580541,3817748708,14467258261,
%U 54975581389,209430786244,799644820201,3059510616421,11728124029611
%N a(n) = ceiling(4^n/n).
%H Vincenzo Librandi, <a href="/A129788/b129788.txt">Table of n, a(n) for n = 1..1000</a>
%t Table[Ceiling[4^n/n],{n,30}] (* _Harvey P. Dale_, Jan 21 2012 *)
%o (Magma) [Ceiling(4^n/n):n in [1..30]]; // _Vincenzo Librandi_, Oct 03 2011
%Y Cf. A053638.
%K nonn,easy
%O 1,1
%A _Mohammad K. Azarian_, May 18 2007