Colin, the hero of this book dated only girls named Katherine, and all break up with him, freshly dumbed by number 19 in the row, he is devestated and goes on a road trip with his best friend. They find jobs in one small town and stay. Colin meets Lindsey (no Katherine!) and starts his work on a theorem about relationships, dumbers and dumpees.
As usual I loved John Green's writing style, he really stands out in the Young Adult genre with far too many mediocre or badly written books.
I also really enjoyed the math references and above all the annotations, really funny and clever. This taught me to never skip over annotations again!
The story itself was ok, but I was never hooked, the characters were likeable but forgettable.
This is a quick and fun read, quite different from the other John Green books I read so far, but again clearly worth picking up!