The magic of nine

yn - ny = 9*(y-n)

y = 1, 2, 3,....,9
n = 1, 2, 3,....,9

Condition: 'y' must not be identical to 'n'

E.g., y = 5, n = 2 => yn = 52 (NOT 5*2=10)

DavidNV (c)2010

(You may post your thoughts / arguments in the comments link below.)

Stress Relaxation of a Twaron®/Natural Rubber Composite
Journal of Engineering Materials and Technology (Transactions of the ASME) 133, 011001:1-9 (2011)

http://link.aip.org/link/?JEMTA8/133/11001/1