## I can't solve it

For students of class 9-10 (age 14-16)
Shapnil
Posts: 10
Joined: Mon Dec 19, 2011 2:05 pm

### I can't solve it

A series is formed in the following manner
A(1)=1
A(n)=f(m) numbers of f(m)followed by f(m) numbers of 0;
m is the number of digits in A(n-1)
Find A(30). Here f(m) is the remainder when m is divided by 9
I can't solve this.Plz help.

*Mahi*
Posts: 1175
Joined: Wed Dec 29, 2010 12:46 pm
Location: 23.786228,90.354974
Contact:

### Re: I can't solve it

It's your first post, and so welcome! But it seems you haven't checked out the posting rules yet.
Posted in wrong forum, topic moved.
Posted twice, so duplicate post removed.
And the problem and answer are already in a post in the forum http://www.matholympiad.org.bd/forum/vi ... f=13&t=621 .
Please check the posting rules to make sure that they don't occur again.

Use $L^AT_EX$, It makes our work a lot easier!

nafistiham
Posts: 829
Joined: Mon Oct 17, 2011 3:56 pm
Location: 24.758613,90.400161
Contact:

### Re: I can't solve it

Shapnil wrote:A series is formed in the following manner
A(1)=1
A(n)=f(m) numbers of f(m)followed by f(m) numbers of 0;
m is the number of digits in A(n-1)
Find A(30). Here f(m) is the remainder when m is divided by 9
I can't solve this.Plz help.
before posting any problem, try to find it in the forum.like as it was a national problem, u could just get it by finding in the search option.
By the way, Welcome.
$\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0$
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.