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%I #9 Nov 01 2022 15:52:22
%S 2,2,18,71,83,747,1679,7538,22394,65186,177578,370898,1497119,2428283,
%T 5285858,47572722,129918074,274553378,1128916463,2107864523,
%U 6892205234,25794120683,14732727599,132594548391,214986322034,1934876898306,8608610563379,24645805942151,63317186094563,94369472696663
%N Differences between odd powers of 3 and the next smaller square
%H Hugo Pfoertner, <a href="/A201124/b201124.txt">Table of n, a(n) for n = 1..500</a>
%F a(n) = 3^(2*n-1) - floor(sqrt(3^(2*n-1)))^2
%e a(1)=3^1-1^2=2, a(2)=3^3-5^2=27-25=2, a(3)=3^5-15^2=243-225=18
%t #-Floor[Sqrt[#]]^2&/@(3^Range[1,61,2]) (* _Harvey P. Dale_, Nov 01 2022 *)
%Y Cf. A051214
%K nonn
%O 1,1
%A _Hugo Pfoertner_, Nov 27 2011