The question is to prove $$f[x,x,....,x] = \frac{f^{(n)}(x)}{n!}$$
Using the Hermite-Genocchi formula, we can obtain that $$f(x) = f^{(n)}(x){\int..\int}_{\tau_n}dt_1dt_2...dt_n$$ Where $\tau_n = \{(t_1,t_2...,t_n)|t_i \ge 0, \sum_1^nt_i \le 1\}$
How do I show the integral to be $\frac{1}{n!}$?
