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S Aug 15, 2017 at 2:38 history suggested Somos CC BY-SA 3.0
Improved ref to arXiv paper. Punctuation improved.
Aug 15, 2017 at 2:28 review Suggested edits
S Aug 15, 2017 at 2:38
Aug 14, 2017 at 23:47 vote accept d.y
Aug 14, 2017 at 23:36 history edited d.y CC BY-SA 3.0
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Aug 14, 2017 at 23:35 answer added Somos timeline score: 6
Aug 14, 2017 at 23:35 history edited d.y CC BY-SA 3.0
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Aug 14, 2017 at 22:33 comment added d.y Let us continue this discussion in chat.
Aug 14, 2017 at 22:32 comment added d.y I want to attach one image of this lattice path but I don't know how!!
Aug 14, 2017 at 22:25 comment added d.y No, $D(3,3)=5$, consider the table with $3$ rows and columns, and the number of lattice paths from the first columns to the entry $(3,3)$ is equal 5.
Aug 14, 2017 at 22:07 comment added Simon Willerton You've now changed you relation in the question so it doesn't involve $D(n-1, n+1)$. Can you explain what $D(2,3)$ is? You have not defined it. With the definition I would guess it seems to be 2. That would mean that $D(3,3) = 2 + 2 =4 \ne 5$.
Aug 14, 2017 at 22:05 comment added d.y I check the relation in question and fixed it. actually, if we have a table with $n$ rows and $m$ columns and let $D(x,y)$ denoted the number of lattice paths from first column to the entra$(x,y)$ we have $$D(x+1,y)=D(x,y-1)+D(x,y)+D(x,y+1)$$ where $D(x,0)=D(x,m+1)=0$ for all $x\geq 1$ and $y=1,2,\cdots , m$. In the above qustion I consider for specail case $m=n$. Also, $D(n-1,n+1)$ is the number of lattice paths with three steps $(1,1),(1,-1),(1,0)$ from the first columns to the entry $(n-1,n+1)$.
Aug 14, 2017 at 21:56 comment added Simon Willerton You have not read my comment. You have not said what $D(n-1, n+1)$ is. The relation you have written in your comment is not the same as the relation you have written in the question.
Aug 14, 2017 at 21:56 history edited d.y CC BY-SA 3.0
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Aug 14, 2017 at 21:51 comment added d.y $D(n,n)$ is the number of all lattice paths from the first column to the entry $(n,n)$, then, $$D(n,n)=D(n-1,n)+D(n-1,n-1)$$.
Aug 14, 2017 at 21:45 comment added Simon Willerton What is $D(n-1, n+1)$? You seem only to have defined $D(n,n)$. If it means what it seems to mean then how can your relation for $D(n,n)$ involve $D(n-1,n+1)$ as that would seem to involve your path leaving the square $T_{n,n}$.
Aug 14, 2017 at 20:52 history asked d.y CC BY-SA 3.0