Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #16 Sep 08 2022 08:45:13
%S 1,3,6,13,27,55,110,221,443,886,1773,3547,7094,14188,28377,56755,
%T 113511,227023,454046,908093,1816186,3632373,7264747,14529495,
%U 29058990,58117981,116235962,232471924,464943848,929887696,1859775393,3719550786
%N a(n) = floor(sqrt(3)*2^(n-1)).
%H Vincenzo Librandi, <a href="/A094386/b094386.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A022838(2^(n-1)). - _R. J. Mathar_, Oct 22 2011
%t Table[Floor[Sqrt[3] 2^(n-1)], {n, 40}] (* _Vincenzo Librandi_, Sep 20 2017 *)
%o (Magma) [Floor(2^(n-1)*Sqrt(3)): n in [1..40]]; // _Vincenzo Librandi_, Sep 20 2017
%o (PARI) a(n) = floor(sqrt(3)*2^(n-1)); \\ _Michel Marcus_, Sep 20 2017
%o (Python)
%o from math import isqrt
%o def A094386(n): return isqrt(3*(1<<(n-1<<1))) # _Chai Wah Wu_, Jul 28 2022
%K nonn
%O 1,2
%A _Roger L. Bagula_, Jun 03 2004