Help with syntax

I want to moderate comments from usernames(or emails) that start with ‘3502’ but not for usernames that start with ‘350’

Example of a username I want to be moderated would be 3502000a1 and a username I don’t want to moderate would be 350bloggsj
I’ve tried a couple of combinations but can’t seem to get it to work

thanks

http://ww.wp.xz.cn/plugins/better-moderation/