Primes whose reversed number is also prime

Primes whose reversed number is also prime is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

Task

Find and show here in base ten primes whose reversed number is also prime, where n < 1,000

Ring

<lang ring> load "stdlib.ring" see "working..." + nl see "Primes whose reversed number is also prime:" + nl row = 0

for n = 1 to 1000

   strn = string(n)
   strn = rever(strn)
   strn = number(strn)
   if isprime(n) and isprime(strn)
      see "(" + n + "," + strn + ")" + " "
      row++
      if row%5 = 0
         see nl
      ok
   ok    

next

see nl + "Found " + row + " prime numbers" + nl see "done..." + nl

func rever(str)

    strb = ""
    for n = len(str) to 1 step -1
        strb += str[n]
    next
    return strb

</lang>

Output:

working...
Primes whose reversed number is also prime:
(2,2) (3,3) (5,5) (7,7) (11,11) 
(13,31) (17,71) (31,13) (37,73) (71,17) 
(73,37) (79,97) (97,79) (101,101) (107,701) 
(113,311) (131,131) (149,941) (151,151) (157,751) 
(167,761) (179,971) (181,181) (191,191) (199,991) 
(311,113) (313,313) (337,733) (347,743) (353,353) 
(359,953) (373,373) (383,383) (389,983) (701,107) 
(709,907) (727,727) (733,337) (739,937) (743,347) 
(751,157) (757,757) (761,167) (769,967) (787,787) 
(797,797) (907,709) (919,919) (929,929) (937,739) 
(941,149) (953,359) (967,769) (971,179) (983,389) 
(991,199) 
Found 56 prime numbers
done...