已知正数满足,则的最小值为 .
已知等比数列{an}是递增数列,Sn是{an}的前n项和,若a1,a3是方程x2-5x+4=0的两个根,则S6=________.
若数列{an}满足lgan+1=1+lgan,a1+a2+a3=10,则lg(a4+a5+a6)=________.
等比数列{an}的前n项和为Sn,已知S3=a2+10a1,a5=9,则a1=________.
若数列{an}的前n项和为Sn=an+,则数列{an}的通项公式是an=________.
已知数列{an}满足3an+1+an=0,a2=-,则{an}的前10项和为________.