by John Green
Colin Singleton, former child prodigy, is attracted to girls named Katherine. Unfortunately, he's also been dumped by every Katherine - 19 times in a row. After the latest dumping, his friend Hassan suggests a roadtrip. They end up in Gutshot, Tennessee, where Colin works on his Theorem of Underlying Katherine Predictability, which should predict the future of any relationship. He also meets Lindsey Lee Wells, who helps him with his theorem, leading to an eureka moment: that the future is infinite, unknowable, and beautiful.
Colin's anagrams (his special talent), quirky footnotes, and mathematical graphs (explained in the appendix) make for a funny, entertaining read.