c:\@Work\Perl\monks\Polyglot>perl non_sequential_pages_1.pl
[[pg. 1 one two  pg. 2 two three four  pg.
4 four five  pg. 5 five
six  pg. 6 six seven eight nine  pg. 9
 nine ten  pg. 10
ten eleven twelve thirteen fourteen  pg. 14 fourteen
 fifteen  pg.
15 fifteen sixteen seventeen  pg.
17 seventeen eighteen nineteen
pg. 19 nineteen and out
]]

((pg. 1 one two  pg. 2 two three four  (PAGE 3 MISSING)  pg.
4 four five  pg. 5 five
six  pg. 6 six seven eight nine  (PAGES 7 - 8 MISSING)  pg. 9
 nine ten  pg. 10
ten eleven twelve thirteen fourteen  (PAGES 11 - 13 MISSING)  pg. 14 fourteen
 fifteen  pg.
15 fifteen sixteen seventeen  (PAGE 16 MISSING)  pg.
17 seventeen eighteen nineteen
(PAGE 18 MISSING)  pg. 19 nineteen and out
))