**Conjecture**

> Let $m$ be give positive integer numbers,a sequence $p_{1},p_{2},\cdots $of primes satisfies the following condition:for $n\ge 3$,$p_{n}$ is the greatest prime divisor $p_{n-1}+p_{n-2}+m$, Prove that the sequence is bounded.

I have solved it when $m$ is even number, but for $m$ is odd, I can't solve it.

When $m$ is even, let $b_{n}=\max\{p_{n},p_{n+1}\}$ for $n\ge 1$

**Lemma:** for all $n$ we have $$b_{n+2}\le b_{n}+m+2$$

**Proof:** certainly $p_{n+1}\le b_{n}$, so it suffices to show that $p_{n+2}\le b_{n}+m+2$. If either $p_{n}$ or $p_{n+1}$ equals $2$, then we have
$$p_{n+2}\le p_{n}+p_{n+1}+m=b_{n}+m+2$$
otherwise, $p_{n}$ and $p_{n+1}$ are both odd, so $p_{n}+p_{n+1}+m$ is even. Because $p_{n+2}\neq 2$ divides this number, we have
$$p_{n+2}\le\dfrac{1}{2}(p_{n}+p_{n+1}+m)\le b_{n}+\frac{m}{2}$$
This proves the claim.

Choose $k$ large enough so that $b_{1}\le k\cdot (m+3)!+1$. We prove by induction that $b_{n}\le k\cdot (m+3)!+1$ for all $n$. If this statement holds for some $n$, then
$$b_{n+1}\le b_{n}+m+2\le k\cdot (m+3)!+m+3$$
if $b_{n+1}>k\cdot (m+3)!+1$ ,then let $q=b_{n+1}-k\cdot (m+3)!$, we have
$1<q\le m+3$, so we have $q|(m+3)!$, hence, $q$ is proper divisor of $k\cdot (m+3)!+q=b_{n+1}$, which is impossible, because $b_{n+1}$ is prime.

Thus $p_{n}\le b_{n}\le k\cdot(m+3)!+1$ for all $n$.

**But if $m$ is an odd number, then $p_{n}+p_{n+1}+m$ is an odd number, so we can't have the following inequality:**
$$p_{n+2}\le\dfrac{1}{2}(p_{n}+p_{n+1}+m)!$$.

So how to prove this case?