determine if each sequence is an arithmetic sequence.if the sequence is arithmetic ,find the common difference
问题描述：
determine if each sequence is an arithmetic sequence.if the sequence is arithmetic ,find the common difference
确定每个序列是一个等差数列.如果序列是算术,找到它们的公差
1.1,1,2,3,5,8,.
2.1,2,4,8,16,.
求公差啊( ⊙ o ⊙
答
设其通项为an,则：
1,
an=a(n-1)+a(n-2)(其中a1=1,a2=1,n>=3)
2,
an=2×a(n-1) (其中a1=1,n>=2)公差啊！！！！~~~~(>_