DescendingPrimes

Ring

<lang ring>

load "stdlibcore.ring"

limit = 1000 row = 0

for n = 1 to limit

   flag = 0
   strn = string(n)
   if isprime(n) = 1
      for m = 1 to len(strn)-1
          if number(substr(strn,m)) < number(substr(strn,m+1))
             flag = 1
          ok
      next
      if flag = 1
         row++
         see "" + n + " "
      ok
      if row % 10 = 0
         see nl
      ok
   ok

next </lang> Output: