non decimal counting systems fulfulde language west africa based fives separate words one five 5 1 six 5 2 5 3 5 4 word ten appo indicates putting sets fingers together get 10 1 10 5 4 separate word twenty beleive dialects use ten times two twenty thirty forty etc get 10 x 3 etc separate words hundred thousand 1000 x 1000 probably practical limit sure unique area africa leslie h stennes