Palindromic primes in base 16

Palindromic primes in base 16 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 palindromic primes in base 16, where n < 500

Ring

<lang ring> load "stdlib.ring" see "working..." + nl see "Palindromic primes in base 16:" + nl row = 0 decList = 0:15 baseList = ["0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"] limit = 500

for n = 1 to limit

   hex = decimaltobase(n,16)
   if ispalindrome(hex) and isprime(n)
      see "" + hex + " "
      row = row + 1
      if row%5 = 0
         see nl
      ok
   ok

next

see nl + "Found " + row + " palindromic primes in base 16" + nl see "done..." + nl

func decimaltobase(nr,base)

    binList = [] 
    binary = 0
    remainder = 1
    while(nr != 0)
         remainder = nr % base
         ind = find(decList,remainder)
         rem = baseList[ind]
         add(binList,rem)
         nr = floor(nr/base) 
    end
    binlist = reverse(binList)
    binList = list2str(binList)
    binList = substr(binList,nl,"")  
    return binList

</lang>

Output:

working...
Palindromic primes in base 16:
2 3 5 7 B 
D 11 101 151 161 
191 1B1 1C1 
Found 13 palindromic primes in base 16
done...