Yup, Mr Summers, that’s what Trump said then, without apology. 

There’s a handy listing of some of the lies Trump had spread for the previous 5 years, at:

http://www.cnn.com/2016/09/09/politics/donald-trump-birther/index.html

Here are just a handful over the 5 years:  

*  "Why doesn't he show his birth certificate? There's something on that birth certificate that he doesn't like."

*  “Now, somebody told me -- and I have no idea if this is bad for him or not, but perhaps it would be -- that where it says 'religion,' it might have 'Muslim.'” 

* "An 'extremely credible source' has called my office and told me that @BarackObama's birth certificate is a fraud."

*  "Who knows about Obama? ... Who knows, who knows? Who cares right now?... I have my own theory on Obama. Someday I will write a book, I will do another book, and it will do very successfully."