// Solver for Rosetta Code problem:
// https://rosettacode.org/wiki/Strange_unique_prime_triplets
//
// This is a good test of the multifor statement where one value relies on
// values to its left, including torture-testing the cases where a lot of
// backtracking is required.  This did not work right until 2025-04-12.

strangePrimes[max, print=false] :=
{
   count = 0
   multifor [n,m,p] = [primes[2,max], primes[n+1,max], primes[m+1,max]]
   {
      sum = n + m + p

      if isPrime[sum]
      {
         count = count + 1
         if print
            println["$n + $m + $p = $sum"]
      }
   }

   println["Found $count unique strange prime triplets up to $max"]
}

strangePrimes[30, true]
strangePrimes[1000, false]