List of 19 ancestors found in 40 iterations (17 distinct persons and 19 positions into tree)

Generation 0 - 1 person(s) on 1 (1 distinct persons)
Generation 1 - 2 person(s) on 2 (2 distinct persons)
2François Ier de Grigny (~1021-)
3Alberthe de Guisy (~1032-~1084)
Generation 2 - 4 person(s) on 4 (4 distinct persons)
Generation 3 - 6 person(s) on 8 (6 distinct persons)
Generation 4 - 4 person(s) on 16 (2 distinct persons)
Generation 5 - 2 person(s) on 32 (2 distinct persons)