return BigInteger.valueOf(LongMath.factorial(n));
    } else {
      int k = 20;
      return BigInteger.valueOf(LongMath.factorial(k)).multiply(oldSlowFactorial(k, n));
    }
  }

  /** Returns the product of {@code n1} exclusive through {@code n2} inclusive. */
  private static BigInteger oldSlowFactorial(int n1, int n2) {
    assert n1 <= n2;
    if (IntMath.log2(n2, CEILING) * (n2 - n1) < Long.SIZE - 1) {

        axesSizeProduct[i] = IntMath.checkedMultiply(axesSizeProduct[i + 1], axes.get(i).size());
      }
    } catch (ArithmeticException e) {
      throw new IllegalArgumentException(
          "Cartesian product too large; must have size at most Integer.MAX_VALUE");
    }
    this.axesSizeProduct = axesSizeProduct;
  }

  private int getAxisIndexForProductIndex(int index, int axis) {

      return BigInteger.valueOf(LongMath.factorial(n));
    } else {
      int k = 20;
      return BigInteger.valueOf(LongMath.factorial(k)).multiply(oldSlowFactorial(k, n));
    }
  }

  /** Returns the product of {@code n1} exclusive through {@code n2} inclusive. */
  private static BigInteger oldSlowFactorial(int n1, int n2) {
    assert n1 <= n2;
    if (IntMath.log2(n2, CEILING) * (n2 - n1) < Long.SIZE - 1) {

        axesSizeProduct[i] = IntMath.checkedMultiply(axesSizeProduct[i + 1], axes.get(i).size());
      }
    } catch (ArithmeticException e) {
      throw new IllegalArgumentException(
          "Cartesian product too large; must have size at most Integer.MAX_VALUE");
    }
    this.axesSizeProduct = axesSizeProduct;
  }

  private int getAxisIndexForProductIndex(int index, int axis) {

        this.session = session;
        this.project = project;
        this.packaging = session.requirePackaging(project.getPackaging());
    }

    public InternalMavenSession getSession() {
        return session;
    }

    public MavenProject getProject() {
        return project;
    }

    @Nonnull
    @Override
    public String getGroupId() {

import java.util.Set;
import java.util.stream.Collectors;

import org.apache.maven.execution.ProjectDependencyGraph;
import org.apache.maven.project.CycleDetectedException;
import org.apache.maven.project.DuplicateProjectException;
import org.apache.maven.project.MavenProject;
import org.apache.maven.project.ProjectSorter;

/**
 * Describes the interdependencies between projects in the reactor.
 *
 */

    private MavenProject project;

    public ProjectArtifact(MavenProject project) {
        super(
                project.getGroupId(),
                project.getArtifactId(),
                project.getVersion(),
                null,
                "pom",
                null,
                new PomArtifactHandler());
        this.project = project;
        setFile(project.getFile());

    private boolean canResume = false;

    public MavenExecutionResult setProject(MavenProject project) {
        this.project = project;

        return this;
    }

    public MavenProject getProject() {
        return project;
    }

    public MavenExecutionResult setTopologicallySortedProjects(List<MavenProject> topologicallySortedProjects) {

    }

    public DefaultDependencyResolutionRequest(MavenProject project, RepositorySystemSession session) {
        setMavenProject(project);
        setRepositorySession(session);
    }

    public DependencyFilter getResolutionFilter() {
        return filter;
    }

    public MavenProject getMavenProject() {
        return project;
    }

    public RepositorySystemSession getRepositorySession() {

     * Registers the specified cache record for usage with the given project. Integrators can use the information
     * collected from this method in combination with a custom cache implementation to dispose unused records from the
     * cache.
     *
     * @param project The project that employs the plugin realm, must not be {@code null}.
     * @param record The cache record being used for the project, must not be {@code null}.
     */