问题
填空题
已知数列{an}中,a1=2,an+1=
|
答案
由题意可得,a1=2=2 1
a2=
=a1 3a1+1
=2 7 2 6+1
a3=
=a2 3a2+1
=2 13 2 2×6+1
a4=
=a3 3a3+1
=2 19 2 3×6+1
故猜想,an=
=2 6(n-1)+1 2 6n-5
故答案为:2 6n-5
已知数列{an}中,a1=2,an+1=
|
由题意可得,a1=2=2 1
a2=
=a1 3a1+1
=2 7 2 6+1
a3=
=a2 3a2+1
=2 13 2 2×6+1
a4=
=a3 3a3+1
=2 19 2 3×6+1
故猜想,an=
=2 6(n-1)+1 2 6n-5
故答案为:2 6n-5