This SELECT allows you to show all sequences on tapes with "Marked for Duplication" set to *YES
SELECT BKHMC,
BKHSYS,
BKHCMD,
BKHLIB,
BKHSEQ,
BKVOL,
BKHSIZ,
BKHDAT,
BKHEXP
FROM QUSRBRM/Q1AHS
WHERE BKDUPSTS = '1'
ORDER BY BKVOL