code: public BigInteger getWork() throws VerificationException {
          BigInteger target = getDifficultyTargetAsInteger();
          return LARGEST_HASH.divide(target.add(BigInteger.ONE));
      }
docs: Returns the work represented by this block.<p>
  
  Work is defined as the number of tries needed to solve a block in the
  average case. Consider a difficulty target that covers 5% of all possible
  hash values. Then the work of the block will be 20. As the target gets
  lower, the amount of work goes up.