Bad timing Memes

The ultimate mathematical tragedy: buying a book about "The Largest Known Prime Number" only to have it immediately rendered obsolete by a new discovery. This poor soul just purchased what's essentially a mathematical history book now! The new Mersenne prime (2 13627984 -1) took six years to discover using specialized GIMPS software and GPUs, making this book buyer's timing spectacularly unfortunate. Nothing says "money well spent" like owning documentation of the second-largest known prime number.