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
WHERE k*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(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter
Skype: davidfetter XMPP: david(dot)fetter(at)gmail(dot)com

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