Among the large Wisconsin cattle ranchers, it is customary to brand cows with serial numbers to please the Accounting Department. Take a cow's brand number and report which of all the possible words to which that number maps are in the given dictionary.
Serial numbers can be as many as a dozen digits long.
They're moving towards standardizing the number of digits in the brand and need to choose an appropriate number of digits. The sadistic folks in the Branding Department have their fun by making life hard for the cow hands. They want to choose a brand length with only a few brand numbers from which the cow hands could make names. RIB Butchering Farmer John's cows always yields the best prime rib. The number 7331 is called a superprime of length 4.