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%I #4 Jun 09 2019 13:09:35
%S 2,-1,2,-3,4,-6,12,-28,64,-136,272,-528,1024,-2016,4032,-8128,16383,
%T -32878,65621,-130188,256158,-497420,946352,-1748000,3100078,-5200300,
%U 8048666,-10897033,10897061,-435,-41847869,161227527,-461566314,1165457645,-2740966304
%N First term of n-th difference sequence of (round(k*sqrt(3))), k >= 0.
%H Clark Kimberling, <a href="/A325841/b325841.txt">Table of n, a(n) for n = 1..200</a>
%t Table[First[Differences[Table[Round[Sqrt[3]*n], {n, 0, 50}], n]], {n, 1, 50}]
%Y Cf. A325664.
%K easy,sign
%O 1,1
%A _Clark Kimberling_, Jun 09 2019