Problem with RewriteCond %{QUERY_STRING}, backreference not dispaying in final URL

I have the following in my .htaccess file:

RewriteCond %{QUERY_STRING} ^route\=pro开发者_Go百科duct\/category\&path\=35\&page\=([0-9]+)$
RewriteRule ^index\.php$ http://%{HTTP_HOST}/product/category/35/page_$1? [R=301,L]

It's not behaving as expected though, when I enter the URL:

http://example.com/index.php?route=product/category&path=35&page=2

It gets rewritten to:

http://example.com/product/category/35/page_

Could someone tell me what I have done wrong please?

Thanks,

eb_dev

---

To reference submatches of a RewriteCond directive, you need to use %n instead of $n:

RewriteCond %{QUERY_STRING} ^route=product/category&path=35&page=([0-9]+)$
RewriteRule ^index\.php$ /product/category/35/page_%1? [R=301,L]