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.

## I can't solve it

### 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.

http://www.matholympiad.org.bd/forum/vi ... p?f=25&t=6

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.

http://www.matholympiad.org.bd/forum/vi ... p?f=25&t=6

Please read Forum Guide and Rules before you post.

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Nur Muhammad Shafiullah | Mahi

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

Nur Muhammad Shafiullah | Mahi

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### Re: I can't solve it

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.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.

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.

Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.