(cleaning up this post sorry if someone saw my previous iteration) actually there is no concrete value for the sum of the natural numbers since it's a divergent series! i cant watch the video now but i'm fairly familiar with the concept, and i think they apply a technique used to derive a value for the sum of a divergent series, which can have some value in theoretical contexts, but in reality is basically completely meaningless. logically, if you had to reference a value for the sum of all natural numbers in any real world context, you would probably use infinity, because that's the limit of the summation of the series as you approach infinity: https://www.wolframalpha.com/input/...n+of+n+from+n=1+to+x+as+x+approaches+infinity