Amount of P-smooth numbers inside a given interval

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Edit:

I found a proof by P. Erdös in "A theorem of Sylvester and Schur".

Any suggestion to prove one of this problems?

The following problems are equivalent:

  1. Prove that for all naturals $n, m : 1 \le n \le m$ then exists a prime $p > n$ such that: $$p \, |\,\prod_{k = 1}^{n}(m+k)$$

  2. Prove that for all naturals $n, m : 1 \le n \le m$ then: $$ \sum_{p\,\text{prime}}\left\lfloor \binom{n + m}{m} \frac{n!}{p} \right\rfloor - \left\lfloor \frac{n!}{p} \right\rfloor > 0 $$

  3. Prove that for all naturals $n, m : 1 \le n \le m$ then: $$ \omega\left(\prod_{k = 1}^{n}(m+k)\right) > \pi(n) $$

    where $\omega$ is the Prime omega function and $\pi$ is the Prime counting function.

    By Bertrand's postulate, for $m = n,\ n+1,\ n+2,\ n + 3$ this is true.

  4. Let $\Psi(x,y)$ the number of y-smooth numbers less than or equal to x.

    Prove that for all naturals $n, m : 1 < n \le m$ then: $$\Psi(m + n, n) - \Psi(m, n) < n$$

    As a corollary of the Størmer's theorem exists a natural $M_n$ such that for all $m \ge M_n$ this is true.


Remark: I don't know if this is true or not, just saw the first one on internet.

Any idea? Is a conjecture writted in another way or something?