题目内容
若
为![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212858890419.png)
的各位数字之和,如
,
,则
;记
,
,…,
,
, 则
▲ .
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212858859467.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212858890419.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212858906607.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212858937566.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212858968493.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212858968577.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212858999607.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212859015739.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212859031814.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212859062518.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140823/20140823212859077616.png)
5
解:f1(8)=f(8)=64+1=656+5=11
f2(8)=f[f1(8)]=f(11)=121+1=122=1+2+2=5
f3(8)=f[f2(8)]=f(5)=25+1=26=8
f4(8)=f[f3(8)]=f(8)
…
所以f2012(8)=f2(8)=5
f2(8)=f[f1(8)]=f(11)=121+1=122=1+2+2=5
f3(8)=f[f2(8)]=f(5)=25+1=26=8
f4(8)=f[f3(8)]=f(8)
…
所以f2012(8)=f2(8)=5
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目