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%I #11 Nov 26 2014 23:03:12
%S 0,0,2,4,6,9,13,18,23,29,35,42,50,58,67,76,87,98,109,121,134,147,161,
%T 176,191,207,224,241,259,277,296,316,337,358,379,402,424,448,472,497,
%U 523,549,575,603,631,660,689,719,749,781,812,845,878,912,946,981,1017,1053,1090
%N Floor of area enclosed in the interior of n unit circles arranged in a circle.
%C See illustration in links.
%H Kival Ngaokrajang, <a href="/A247179/a247179.pdf">Illustration of initial terms</a>
%F a(n) = Floor((n/tan(Pi/n)) - Pi*((n/2)-1)).
%o (PARI)for (n=3,100,print1(floor((n/tan(Pi/n))-Pi*((n/2)-1)),", "))
%K nonn
%O 3,3
%A _Kival Ngaokrajang_, Nov 22 2014