Possible pagination issue

I noticed recently that google had cached an interesting page on my site. I was my home page, however, the URL was https://www.mysite.com/page/2. I never created a page called 2 with the parent of “page”. I also tried https://www.mysite.com/page/3 as well as with 4, 5, 6, etc… I started googling a bit and came across these two posts:

post 1

post 2

These threads suggest that using a query_post in certain situations may have this impact.

In my situation these didn’t seem to apply because

# grep -r "query_post" .

in my themes directory returned nothing. Does anyone know what could be the case here? I don’t need google caching tons of versions of my homepage. I’m not quite sure how google even found that URL to begin with. Should I simply Disallow it in robots.txt? A more permanent solution would seem ideal.

EDIT: Just for further info, I am using the post name option in my perma link settings.