n前n项和为2An a3*a6=(a1+2d)(a1+5d)=a1^2+7da1+10d^2=55 1
a1+a8=a3+a6d=16 2
16a3-a3^2-55=0
a3= 11 或者 a3=5
则 a6=5或者a6=11
an递增 a3
数列{A n}为递增等差数列,且A3×A6=55,A1+A8=16.若An=B1/2+B2/2+……+Bn/2,求数列{
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