# What does the following recurrence formula represent

I know that :

$$T(n,k)=T(n−1,k−1)+T(n−1,k)$$ is the Pascal triangle.

But what is this then:

$$T(n,k)=T(n−1,k−1)+T(n,k-1)$$

Is there any name for it? I am trying to learn about it's time complexity etc, but I can't find anything online.

• What is the time complexity of a recurrence? Time complexity is usually associated with algorithms: it describes the asymptotic rate of growth of their running time. May 3 at 2:53
• You might find it useful to know about oeis.org
– D.W.
May 3 at 3:23
• Let $T'(n,m):=T(m,n)$. Rewrite the second recurrence. May 3 at 12:34