DECLARE @n INT = 1000;

WITH numbers AS (
    SELECT 2 AS num
    UNION ALL
    SELECT num + 1 FROM numbers WHERE num + 1 <= @n
)


,primes_num as (

SELECT *
FROM numbers 

where not EXISTS  (select * from numbers inners where 

numbers.num % inners.num=0 and numbers.num <> inners.num)
)
select STRING_AGG(num,'&') from primes_num


OPTION (MAXRECURSION 1000)