grandparent                   great(x10)grandparent         great(x20)grandparent         great(x30)grandparent         great(x40)grandparent         great(x50)grandparent         great(x60)grandparent         great(x70)grandparent
              |                             |                             |                             |                             |                             |                             |                             |
        1..2..3..4..5..6..7..8..9..10.11.12.13.14.15.16.17.18.19.20.21.22.23.24.25.26.27.28.29.30.31.32.33.34.35.36.37.38.39.40.41.42.43.44.45.46.47.48.49.50.51.52.53.54.55.56.57.58.59.60.61.62.63.64.65.66.67.68.69.70.71.72.73.74.75.76.77.78.79.80