code: public static double largeEstimator(final int log2m, final int registerSizeInBits, final double estimator) {
          final double twoToL = TWO_TO_L[(REG_WIDTH_INDEX_MULTIPLIER * registerSizeInBits) + log2m];
          return -1 * twoToL * Math.log(1.0 - (estimator/twoToL));
      }
docs: The "large range correction" formula from the HyperLogLog algorithm, adapted
  for 64 bit hashes. Only appropriate for estimators whose value exceeds
  the return of {@link #largeEstimatorCutoff(int, int)}.
  
  @param  log2m log-base-2 of the number of registers in the HLL. <em>b<em> in the paper.
  @param  registerSizeInBits the size of the HLL registers, in bits.
  @param  estimator the original estimator ("E" in the paper).
  @return a corrected cardinality estimate.
  @see <a href='http://research.neustar.biz/2013/01/24/hyperloglog-googles-take-on-engineering-hll/'>Blog post with section on 64 bit hashes and "large range correction"</a>