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

ꯈꯟꯒꯠꯂꯕ ꯈꯦꯠꯅꯕ:ꯑꯃꯨꯛꯍꯟꯅ-ꯌꯦꯡꯕꯁꯤꯡ ꯆꯥꯡꯗꯝꯅꯅꯕ ꯔꯤꯗꯤꯑꯣ ꯅꯝꯐꯝꯁꯤꯡꯗꯨ ꯍꯛꯆꯤꯟꯂꯨ ꯑꯃꯁꯨꯡ ꯏꯟꯇꯔꯗ ꯅꯝꯃꯣ ꯅꯠꯇ꯭ꯔꯒ ꯈ꯭ꯋꯥꯏ ꯃꯈꯥꯒꯤ ꯅꯝꯐꯝꯗꯨ ꯅꯝꯃꯨ ꯫
ꯂꯤꯖꯦꯟ: (ꯍꯧ) = ꯈꯦꯠꯅꯕꯁꯤꯡ ꯂꯣꯏꯅꯅ ꯈ꯭ꯋꯥꯏꯗꯒꯤ ꯑꯅꯧꯕ ꯱ꯑꯃꯨꯛꯍꯟꯅ-ꯌꯦꯡꯕ, (ꯃꯃꯥꯡꯒꯤ) = ꯃꯊꯪ ꯃꯊꯪ ꯂꯥꯛꯄ ꯑꯃꯨꯛꯍꯟꯅ-ꯌꯦꯡꯕꯒ ꯂꯣꯏꯅꯅ ꯈꯦꯠꯅꯕꯁꯤꯡ, ꯃ = ꯑꯄꯤꯛꯄ ꯁꯦꯝꯒꯠꯄꯅꯤ ꯫