m20:=ma(c,20);cref(m20,1);
ref(cross(v,ma(v,5)) and cross(v,ma(v,20)) and cross(v,ma(v,60)),1) and v
count(cross(ma(c,20),c),3)=1 and cross(c,ma(c,20));
股价跌破20均线后多长时间有要求吗？今天收盘价刚收在20均线上，上多少有限制吗？
