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A105224 Number of squares between n and 2n inclusive. 1

%I

%S 1,1,1,1,1,1,1,2,2,1,1,1,2,2,2,2,1,2,2,2,2,2,2,2,3,2,2,2,2,2,2,3,3,3,

%T 3,3,2,2,2,2,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,3,3,3,3,

%U 3,3,3,4,4,4,4,4,4,4,4,4,4,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,5,5,5,4,4,4,4,4

%N Number of squares between n and 2n inclusive.

%C a(n)>=1 because between n and 2n there is always at least one square.

%F a(n) = A000196(2n) - A000196(n-1).

%e a(8)=2 because between 8 and 16 there are two squares: 3^2 and 4^2.

%t f[n_] := Floor[Sqrt[n]]; Table[f[2n] - f[n - 1], {n, 100}]

%Y Cf. A000196, A105223.

%K easy,nonn

%O 1,8

%A _Giovanni Teofilatto_, Apr 14 2005

%E Edited and extended by _Ray Chandler_, Apr 16 2005

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Last modified May 23 17:52 EDT 2013. Contains 225611 sequences.