set enable_seqscan=off;
CREATE TABLE test_int4 (
	i int4
);
INSERT INTO test_int4 VALUES (-2),(-1),(0),(1),(2),(3);
CREATE INDEX idx_int4 ON test_int4 USING gin (i);
SELECT * FROM test_int4 WHERE i<1::int4 ORDER BY i;
 i  
----
 -2
 -1
  0
(3 rows)

SELECT * FROM test_int4 WHERE i<=1::int4 ORDER BY i;
 i  
----
 -2
 -1
  0
  1
(4 rows)

SELECT * FROM test_int4 WHERE i=1::int4 ORDER BY i;
 i 
---
 1
(1 row)

SELECT * FROM test_int4 WHERE i>=1::int4 ORDER BY i;
 i 
---
 1
 2
 3
(3 rows)

SELECT * FROM test_int4 WHERE i>1::int4 ORDER BY i;
 i 
---
 2
 3
(2 rows)