You certanly don't want to expose a 6 table join (and on top of that even using dictionary tables directly!) just to extract grants on sequences? Grants on sequences are available through USER/ALL/DBA_TAB_PRIVS, just as any other object grants. So something like this:

SELECT 'GRANT SELECT ON '||p.owner||'.'||p.table_name||' TO '||p.grantee stmt
FROM DBA_TAB_PRIVS p, DBA_SEQUENCES s
WHERE p.owner = s.sequence_owner
AND p.table_name = s.sequence_name
AND s.sequence_owner = 'ABC';