Revision history of "an empty string is not a natural number" (Z13498)

ⴰⵙⵜⴰⵢ ⵏ ⵓⵎⵣⴰⵔⴰⵢ : ⵕⵛⵎ ⵜⴰⵏⴽⵓⵍⵉⵏ ⵏ ⵜⵓⵏⵖⵉⵍⵉⵏ ⵏⵏⴰ ⵜⵔⵉⴷ ⴰⴷ ⵜⵙⵎⵣⴰⵣⴰⵍⴷ ⵜⴰⴷⵔⴷ ⵉ ⴰⴽⵎ ⵏⵖ ⵉ ⵜⵙⴰⵔⵓⵜ ⵏ ⵢⵉⵣⴷⴰⵔ.
ⵜⴰⴱⴰⴷⵓⵜ : (ⵎⵔⵏ) = ⴰⵎⵣⴰⵔⴰⵢ ⴰⴽⴷ ⵜⵓⵏⵖⵉⵍⵜ ⵜⴰⵎⴳⴳⴰⵔⵓⵜ, (ⵓⵣⵡⵉⵔ) = ⴰⵎⵣⴰⵔⴰⵢ ⴰⴽⴷ ⵜⵓⵏⵖⵉⵍⵜ ⵉⵣⵔⵉⵏ, ⵎ = ⵉⵙⵏⵉⴼⵉⵍⵏ ⵉⵎⵥⵥⵉⵢⵏ.