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%I #17 Oct 21 2013 12:39:57
%S 0,0,2,3,5,4,10,14,15,20,20,29,37,43,38,49,63,66,85,71,83,102,116,125,
%T 118,146,153,162,176,179,193,223,246,253,233,254,295,315,326,339,355,
%U 342,418,418,405,446,474,493,506,518,539,612,602,631,598,644,700
%N Sum of all k from {1,...,n} such that the fractional part of n/k is contained in the open interval (1/4, 3/4).
%C Differs from A227912 because the inequalities are strict.
%e a(5)=5, the valid k such that frac(5/k) is an element of (1/4,3/4) are 2 and 3, 2+3=5.
%o (JavaScript)
%o for (i=1;i<50;i++) {
%o c=0;
%o for (j=1;j<=i;j++) {
%o v=Math.floor(i/j);
%o if (i/j-v>0.25 && i/j-v<0.75) c+=j;
%o }
%o document.write(c+", ");
%o ;
%o }
%Y Cf. A227912.
%K nonn
%O 1,3
%A _Jon Perry_, Oct 13 2013
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