Special neighbor primes

Special neighbor primes 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

Let   (p₁,  p₂)   are primes. Find and show here in base ten p₁,   p₂   - 1   where   p₁,   p₂  <  100.

Ring

<lang ring> load "stdlib.ring"

see "working..." + nl see "Special twin primes are:" + nl row = 0 oldPrime = 2

for n = 3 to 100

   if isprime(n) and isprime(oldPrime) 
      sum = oldPrime + n - 1
      if isprime(sum)
         row++
         see "" + oldPrime + "," + n + " => " + sum + nl
      ok
      oldPrime = n
   ok

next

see "Found " + row + " special twin primes" see "done..." + nl </lang>

Output:

working...
Special twin primes are:
3,5 => 7
5,7 => 11
7,11 => 17
11,13 => 23
13,17 => 29
19,23 => 41
29,31 => 59
31,37 => 67
41,43 => 83
43,47 => 89
61,67 => 127
67,71 => 137
73,79 => 151
Found 13 special twin primesdone...