I am unsure why parent comment is downvoted. Depending on where you looks, 0 may or may not be included in the set of natural numbers. ---- Lexicon / Oxford D

I am unsure why parent comment is downvoted. Depending on where you looks, 0 may or may not be included in the set of natural numbers. ---- Lexicon / Oxford Dictionary https://www.lexico.com/en/definition/natural_numbers https://www.lexico.com/en/definition/natural_numbers > The positive integers (whole numbers) 1, 2, 3, etc., and sometimes zero as well. ---- Wikipedia https://en.wikipedia.org/wiki/Natural_number https://en.wikipedia.org/wiki/Natural_number > Some definitions, including the standard ISO 80000-2,begin the natural numbers with 0, corresponding to the non-negative integers 0, 1, 2, 3, ... ---- Math World / Wolfram https://mathworld.wolfram.com/NaturalNumber.html https://mathworld.wolfram.com/NaturalNumber.html > The term "natural number" refers either to a member of the set of positive integers 1, 2, 3, ... (OEIS A000027) or to the set of nonnegative integers 0, 1, 2, 3, ...