Forbidden number...uuuuuhhh ~

Ok so...i was messing around with a player in my pt , and by writing randoms numbers i found out that one is censured...i tried to google it but i can't find anything usefull about it...so since here i can for sure find some veteran-allknowledging players this is my question :



Why the heck is the number 9-2-3 censured in game? ... and also nickel-back seems to be censured...poor guys O_o