Search: id:A157001 Results 1-1 of 1 results found. %I A157001 %S A157001 0,1,2,5,7,11,14,21,25,32,37,47,53,63,70,85,93,106,115,132,142,158,169, %T A157001 191,203,222,235,259,273,295,310,341,357,382,399,430,448,476,495,532, %U A157001 552,583,604,642,664,698,721,767,791,828,853,898,924,964,991,1043,1071 %N A157001 Fractions x/y, with 1<=x,y<=n, that reduce to (odd)/(even). %C A157001 Equivalently, a(n) is the number of fractions x/y, with 1<=x,y<=n, that reduce to (even)/(odd). %Y A157001 a(n)=(n^2-A135013)/2 %Y A157001 Sequence in context: A099835 A133436 A001225 this_sequence A134640 A032616 A006066 %Y A157001 Adjacent sequences: A156998 A156999 A157000 this_sequence A157002 A157003 A157004 %K A157001 nonn %O A157001 1,3 %A A157001 Adam McDougall (mcdougall.adam(AT)gmail.com), Feb 20 2009 Search completed in 0.001 seconds