# t-design

• Jun 1st 2010, 04:30 AM
bram kierkels
t-design
I want to show that if the t-design $3-(v,6,1)$, that is the Steinersystem $S(3,6,v)$, exist then $v \equiv_{20} 2$ or $v \equiv_{20}6$.

My first step is to calculate $b_{i} = \lambda \frac{\left(\begin{array}{cc}v-i\\t-i\end{array}\right)}{\left(\begin{array}{cc}k-i\\t-i\end{array}\right)} \forall$ $0\leq i \leq3$

How can I use these numbers to show that $v \equiv 2$ or $6$ mod $20$?

Thanks
• Jun 2nd 2010, 10:17 PM
gmatt
Quote:

Originally Posted by bram kierkels
I want to show that if the t-design $3-(v,6,1)$, that is the Steinersystem $S(3,6,v)$, exist then $v \equiv_{20} 2$ or $v \equiv_{20}6$.

My first step is to calculate $b_{i} = \lambda \frac{\left(\begin{array}{cc}v-i\\t-i\end{array}\right)}{\left(\begin{array}{cc}k-i\\t-i\end{array}\right)} \forall$ $0\leq i \leq3$

How can I use these numbers to show that $v \equiv 2$ or $6$ mod $20$?

Thanks

Questions like these have close to zero chance of being answered because you don't give definitions for the different terms you are using, and clearly what you are discussing requires very specific domain knowledge.

For a better chance at receiving an answer, make sure you define the terms you use or at the very least point to a website with complete definitions of all the terms you use.
• Jun 3rd 2010, 02:34 AM
bram kierkels
Quote:

Originally Posted by gmatt
Questions like these have close to zero chance of being answered because you don't give definitions for the different terms you are using, and clearly what you are discussing requires very specific domain knowledge.

For a better chance at receiving an answer, make sure you define the terms you use or at the very least point to a website with complete definitions of all the terms you use.

If I give exact definitions for the terms you still need very specific domain knowledge. So either you know what a t-design and a Steinersystem is, or you don't. Otherwise I have to include a complete chapter on Steinersystems with all her theorems and definitions.
• Jun 3rd 2010, 09:54 AM
gmatt
Quote:

Originally Posted by bram kierkels
If I give exact definitions for the terms you still need very specific domain knowledge. So either you know what a t-design and a Steinersystem is, or you don't. Otherwise I have to include a complete chapter on Steinersystems with all her theorems and definitions.

Fair enough, its worth a try I guess. Though, there are some pretty bright people on these forums and if you give some definitions it may just improve your chances.