The program does not check record types for a special sequence (positions
17 and 18 have alphabetic entries).
1
Only one record of this type can be present in the sequenced group.
N
One or more records of this type can be present in the sequenced group.
This entry must be used when a numeric entry is made in positions 17 and
18. If an alphabetic entry is made in positions 17 and 18, this entry must
be blank.