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%I #12 Jun 20 2024 11:08:05
%S 0,1,4,4,9,9,9,16,16,16,16,25,25,25,25,25,36,36,36,36,36,36,49,49,49,
%T 49,49,49,49,64,64,64,64,64,64,64,64,81,81,81,81,81,81,81,81,81,100,
%U 100,100,100,100,100,100,100,100,100,121,121,121,121,121,121,121,121,121
%N Squares closest to 2*n.
%H Vincenzo Librandi, <a href="/A168038/b168038.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = A002024(n)^2. - _Chai Wah Wu_, Jun 19 2024
%t Round[Sqrt[2*Range[0,120]]]^2
%o (Python)
%o from math import isqrt
%o def A168038(n): return (isqrt(n<<3)+1>>1)**2 # _Chai Wah Wu_, Jun 19 2024
%Y Cf. A002024, A093995.
%Y Essentially partial sums of A198954.
%K nonn
%O 0,3
%A _Zak Seidov_, Nov 17 2009