问题标题:
【数列{an}中有a1=1,a(n+3)=an+3,a(n+2)≥an+2(n∈N*)(1)求a7,a5,a3,a6;】
问题描述:

数列{an}中有a1=1,a(n+3)=an+3,a(n+2)≥an+2(n∈N*)(1)求a7,a5,a3,a6;

李金铠回答:
  a(3)>=a(1)+2   a(5)>=a(3)+2   a(7)>=a(5)+2   a(7)>=a(1)+6   a(7)=a(4)+3=a(1)+3+3=a(1)+6   所以全部取等   a(3)=a(1)+2   a(5)=a(3)+2   a(7)=a(5)+2   a(3)=3   a(5)=5   a(7)=7   a(3)>=a(1)+2   a(5)>=a(3)+2   a(7)>=a(5)+2   a(9)>=a(7)+2   a(11)>=a(9)+2   a(13)>=a(11)+2   a(15)>=a(13)+2   a(17)>=a(15)+2   a(19)>=a(17)+2   a(19)>=a(1)+18   a(19)=a(16)+3=a(13)+6=a(10)+9=a(7)+12=19   所以以上全取等   a(15)=a(12)+3=a(9)+6=a(7)+2=9   a(6)=a(9)-3=6
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