数列{an}满足an+1=an-3(n>=1)且a1=7,则a3的值是

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数列{an}满足an+1=an-3(n>=1)且a1=7,则a3的值是数列{an}满足an+1=an-3(n>=1)且a1=7,则a3的值是数列{an}满足an+1=an-3(n>=1)且a1=7,则

数列{an}满足an+1=an-3(n>=1)且a1=7,则a3的值是
数列{an}满足an+1=an-3(n>=1)且a1=7,则a3的值是

数列{an}满足an+1=an-3(n>=1)且a1=7,则a3的值是
a2=a1-3=7-3=4
a3=a2-3=4-3=1

a(n+1)=an-3
a(n+1)-an=-3
∴数列是等差数列,公差d=-3
a3=a1+(3-1)d
=7+2*(-3)
=1