Deposits a value for the last transaction sequence number (TSN)
    to enable snapshot (.snp) files for the logical area of the AIP
    entry.

                                   NOTE

       Beginning in Oracle Rdb V7.0, Oracle Rdb stores any
       transaction sequence number that is larger than a longword
       by using both the TSN field on the page and the page TSN
       base. Oracle Rdb calculates the actual TSN by applying a
       formula to these two values. Oracle Corporation recommends
       that you do not change a TSN value that is larger than a
       longword. When a TSN is larger than a longword, a nonzero
       number is stored in the page TSN base (the page tail). The
       following example shows the location of the page TSN and the
       page TSN base:

                     000A 00000003  0000  page 3, physical area 10
                          9D091204  0006  checksum = 9D091204
                 009A2C0F ED786D2E  000A  time stamp = 23-MAY-1996 09:08:53.36
                         0000 03C4  0012  964 free bytes, 0 locked
                              0001  0016  1 line
                         0005 03E4  0018  line 0: offset 03E4, 5 bytes

       page TSN ----->    00000000  001C  line 0: TSN 0

          .
          .
          .
                              2001  03E4  line 0 (10:3:0) SYSTEM record
                           00 0001  03E6  1 byte in 0 sets/dynamic items
                        0000000000  03E9  padding '.....'

                          FFFFFFFF  03EE  snap page pointer -1
                          00000000  03F2  snap pointer TSN 0
                              0000  03F6  MBZ '..'
                          00000000  03F8  page sequence number 0
       page TSN base -------> 0000  03FC  page TSN base 0
                             0000  03FE  MBZ '..'