Help with Combinatorics

For students of class 9-10 (age 14-16)
Rabeeb
Posts: 25
Joined: Tue Dec 14, 2010 7:52 pm
Location: Mymensingh, Bangladesh
Contact:

Help with Combinatorics

Unread post by Rabeeb » Sat Feb 23, 2013 8:48 pm

What are consistently dominated sequences? (with sufficient examples)

User avatar
nayel
Posts: 268
Joined: Tue Dec 07, 2010 7:38 pm
Location: Dhaka, Bangladesh or Cambridge, UK

Re: Help with Combinatorics

Unread post by nayel » Sun Feb 24, 2013 5:25 pm

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
Posts: 25
Joined: Tue Dec 14, 2010 7:52 pm
Location: Mymensingh, Bangladesh
Contact:

Re: Help with Combinatorics

Unread post by Rabeeb » Sun Feb 24, 2013 5:53 pm

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

sakibtanvir
Posts: 188
Joined: Mon Jan 09, 2012 6:52 pm
Location: 24.4333°N 90.7833°E

Re: Help with Combinatorics

Unread post by sakibtanvir » Wed Feb 27, 2013 1:59 pm

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. :D
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
Location: Mymensingh, Bangladesh
Contact:

Re: Help with Combinatorics

Unread post by Rabeeb » Wed Feb 27, 2013 11:33 pm

Thanks for your help.
Last edited by *Mahi* on Thu Feb 28, 2013 9:27 am, edited 1 time in total.
Reason: Use full forms while writing a reply.

Post Reply