A110916 - OEIS

%I #9 Oct 12 2019 11:53:44

%S 4,1,1,1,1,0,1,0,1,0,1,0,1,0,1,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,0,1,0,

%T 0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,1,

%U 0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0

%N Number of squares between 10n and 10n+9 (inclusive).

%H G. C. Greubel, <a href="/A110916/b110916.txt">Table of n, a(n) for n = 0..5000</a>

%e a(0) = 4 since between 0 and 9 there are 4 squares {0,1,4,9}.

%t f2[n_] := If[n < 0, 0, Floor[n^(1/2)] + 1]; Table[f2[10n + 9] - f2[10n - 1], {n, 0, 120}] (* _Ray Chandler_, Oct 07 2005 *)

%Y Cf. A111025, A111037.

%K nonn

%O 0,1

%A _Giovanni Teofilatto_, Oct 04 2005

%E Extended by _Ray Chandler_, Oct 07 2005