/sys$common/syshlp/helplib.hlb DUMP, Qualifiers, /NUMBER  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /NUMBER[=n]

    Specifies how byte offsets are assigned to the lines of output.
    If you specify the /NUMBER qualifier, the byte offsets increase
    continuously through the dump, beginning with n; if you omit the
    /NUMBER qualifier, the first byte offset is zero. By default, the
    byte offset is reset to zero at the beginning of each block or
    record.