Q: How many IBM types does it take to change a light bulb?

A: Fifteen. One to do it, and fourteen to write document number

GC7500439-0001, Multitasking Incandescent Source System Facility,

of which 10% of the pages state only "This page intentionally

left blank", and 20% of the definitions are of the form "A:.....

consists of sequences of non-blank characters separated by blanks".