You get information on your sequences from user_sequences.
SQL> desc user_sequences;
Name Null? Type
------------------
SEQUENCE_NAME NOT NULL VARCHAR2(30)
MIN_VALUE NUMBER
MAX_VALUE NUMBER
INCREMENT_BY NOT NULL NUMBER
CYCLE_FLAG VARCHAR2(1)
ORDER_FLAG VARCHAR2(1)
CACHE_SIZE NOT NULL NUMBER
LAST_NUMBER NOT NULL NUMBER
last_number:Last number that was generated or cached by the sequence.
SQL>
SQL> CREATE SEQUENCE test_seq
2 START WITH 10 INCREMENT BY -1
3 MINVALUE 1 MAXVALUE 10
4 CYCLE CACHE 5;
Sequence created.
SQL>
SQL> select * from user_sequences where sequence_name='TEST_SEQ';
SEQUENCE_NAME MIN_VALUE MAX_VALUE INCREMENT_BY C O CACHE_SIZE LAST_NUMBER
------------------------------ ---------- ---------- ------------ - - ---------- -----------
TEST_SEQ 1 10 -1 Y N 5 10
SQL>
SQL> drop sequence test_seq
2 /
Sequence dropped.
SQL>