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Apr 5, 2018 at 12:14 vote accept hengxin
Apr 5, 2018 at 11:55 comment added hengxin I have obtained that $A(n,k) = c\binom{n}{k} - c$. Thanks.
Apr 5, 2018 at 11:31 comment added Yuval Filmus Try again. My method works just as well in this case.
Apr 5, 2018 at 11:28 comment added hengxin I just found that I have made a mistake: The initial conditions should be $A(n,0) = A(n,n) = 0$ instead of $A(n,0) = A(n,n) = 1$. $A(n)$ aims to count the number of additions in computing $\binom{n}{k}$ following the identity $\binom{n}{k} = \binom{n-1}{k-1} + \binom{n-1}{k}$. I failed to apply your method with such initial conditions. Therefore, I have removed the code and the backgroud, leaving only the recurrence to solve. However, can you solve this recurrence with the new initial conditions? (Maybe I should open a new post.)
Apr 5, 2018 at 9:30 comment added Yuval Filmus Experience. Perhaps more interesting is to solve the recurrence when $A(n,0) \neq A(n,n)$.
Apr 5, 2018 at 9:29 comment added hengxin Are there any clues for you to guess that $A(n,k) = \alpha \binom{n}{k} + \beta$?
Apr 5, 2018 at 9:12 history answered Yuval Filmus CC BY-SA 3.0