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%I #9 Apr 10 2021 23:58:51
%S 0,0,1,1,2,2,3,4,4,5,5,6,6,7,7,8,9,9,9,10,11,11,12,12,13,13,14,14,15,
%T 15,16,16,16,17,18,18,19,19,19,20,20,21,21,22,23,23,23,24,24,25,25,26,
%U 26,26,27,27,28,28,29,30,30,31,31,32,32,33,34,34,34,35,35,36,36
%N a(n) = floor(Sum_{k=1..n} <2*k*Pi>), where < > = fractional part.
%t r = 2Pi;
%t a[n_] := Floor[Sum[FractionalPart[k*r], {k, 1, n}]]
%t Table[a[n], {n, 1, 90}] (* A194212 *)
%t s[n_] := Sum[a[k], {k, 1, n}]
%t Table[s[n], {n, 1, 100}] (* A194213 *)
%Y Cf. A194213.
%K nonn
%O 1,5
%A _Clark Kimberling_, Aug 19 2011