I am wondering if the word "then" introduces a necessary condition and/or the conclusion to premise(s); and if "then" is only pertinent to conditional statements, or to cause and effect statements, as well. Of note, I am wondering this because the word "then" seems to function similarly to words that I know introduce necessary conditions and conclusions -- such as, "requires" or "must" (for necessary conditions); and "therefore" or "thus" (for conclusions) -- but I do not see "then" on any official list of indicator words that introduce necessary conditions or conclusions.

Thank you!

Michael