" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2025 KUDO.TIPS - All rights reserved.
=4²-1
=15
U5=5²-1
=24
U6=6²-1
=35
15,24,35
U4=7
U5=10-1
U5=9
U6=12-1
U6=11