pThe number might be a person's identification number, and the rest of the record has information about the person.
[ 0 ]
[ 1 ]
[ 2 ]
[ 3 ]
[ 4 ]
[ 5 ]
. . .
[ 700]
[ 4 ]
Number506643548
The numbers might be
identification numbers of some sort, and the rest of the record contains
information about a person. So the pattern that you see here is the same
pattern that you've seen in other dictionaries: Each entry in the dictionary
has a key (in this case an identifying number) and some associated data.