CTE bug?

Folks,

While working to write the Sieve of Eratosthenes using CTEs, I ran
across a strange error, namely that it appears I'm not allowed to nest
WITH.  Is this a bug?

Cheers,
David.

WITH RECURSIVE t1(n) AS (   VALUES(2)
UNION ALL   SELECT n+1 FROM t1 WHERE n < 1000
),
t2 (n, i) AS (   SELECT 2*n+2, 2   FROM t1 WHERE 2*n+2 <= 1000
UNION ALL   WITH t3(k) AS (       SELECT max(i) FROM t2   )   SELECT k*n+k, k   FROM       t1   CROSS JOIN       t3
WHEREk*n+k <= 1000
 
)
SELECT * FROM t1 EXCEPT SELECT n FROM t2 ORDER BY 1;
ERROR:  syntax error at or near "WITH t3"
LINE 10:     WITH t3(k) AS (            ^

-- 
David Fetter <david@fetter.org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
Skype: davidfetter      XMPP: david.fetter@gmail.com

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