adsense for search - the only thing on a site - is't allowed?

I am considering placing adsense for search search boxes to some domains that I am not using at the moment to see if I can get any revenue out of the type-in traffic and their searches via google search box.

I wonder if Google allows the search box to be the only thing on a site. Because I am not going to put any content at all to these sites.

Please kindly advice me and Thanks in advance.

 

http://www.fka200.com/2007/12/10/adsense-for-search-vs-google-co-op/

I wrote about it here.