## Help with Combinatorics

For students of class 9-10 (age 14-16)
Rabeeb
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### Help with Combinatorics

What are consistently dominated sequences? (with sufficient examples)

nayel
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Location: Dhaka, Bangladesh or Cambridge, UK

### Re: Help with Combinatorics

This is not a common mathematical phrase. What is the context of its usage?
"Everything should be made as simple as possible, but not simpler." - Albert Einstein

Rabeeb
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### Re: Help with Combinatorics

nayel wrote:This is not a common mathematical phrase. What is the context of its usage?
I found it in "Combinatorics" by Marcus

sakibtanvir
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### Re: Help with Combinatorics

Look at the following examples,since you are reading Marcus I don't think you will have any problem understanding my languages.
Consider the string:$AABBABA$,Now what you have to do is to make some words cutting from the main string.If you want to cut a $n$ digit word from the main string always cut the word made by initial $n$ digits.Say $n=3$ then we take the blue colored word $AAB$$BABA$.Now we proceed for all values of $n$.(1,2,3,...7).
When,$n=1$ the word(actually letter!) is $A$ & contains one $A$.
$n=2$ the word is $AA$ & contains two $A$'s.
$n=3$,this case is already shown.
$n=4$ the word is $AABB$ and contains two $A$'s.
........
$n=7$ the word contains four $A$'s.Each time if the word build with $n$ initial digits contains $k$ A's then it follows the rule that $k \geq \frac{n}{2}$. That's why $AABBABA$ is called an $A$ dominated sequence.
An amount of certain opposition is a great help to a man.Kites rise against,not with,the wind.

Rabeeb
Posts: 25
Joined: Tue Dec 14, 2010 7:52 pm