1/2*4+1/4*6+...+1/2012*2014=1/4*1/1*2+1/4*1/2*3+1/4*1/3*4...+1/4*1006*1007=1/4*（1/1*2+1/2*3+1/3*4...+1/1006*1007）=1/4*（1+1/2-1/2+1/3-1/3+1/4-1/4.-1/1007）=1/4*（1-1/1007）=1/4*1006/1007=503/2014 另...