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mathstime
Mar5-10, 07:05 AM
Hi

I am looking to show that \binom{|\mathbbm{F}| + n -1}{n} = \frac{1}{n!} |\mathbbm{F}|^n + O(|\mathbbm{F}|^{n-1})

please could someone show me how??

g_edgar
Mar5-10, 09:13 AM
How about writing the problem: for each n,

\binom{u+n-1}{n} = \frac{u^n}{n!} + O(u^{n-1})
\quad \text{as } u \to +\infty


If that is what you mean, first try to prove it for n=1, n=2, n=3 and see
if you understand those.

mathstime
Mar6-10, 07:52 AM
got it! thanks!