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There you go. It got me too. I believe this is the first question I have ran across that uses "exclusive". I'm so used to seeing "inclusive" that I did the same thing you did.

this is the second time i have seen someone use the forumla "(last term - first term)/2 +1 = number of odd or even terms in an arithemtic progression with an odd number of total terms. i think it is important to note it only works when the series is all positive numbers

0,1,2 = how many odd terms? just one. but with your formula (2-0)/2 +1 =2

of course. It only works when all numbers in the series are either all positive or all negative.

If the ZERO is involved, then the whole thing changes because Zero doesn't affect the calculations, yet it counts for an addition element in the series.

of course. It only works when all numbers in the series are either all positive or all negative.

If the ZERO is involved, then the whole thing changes because Zero doesn't affect the calculations, yet it counts for an addition element in the series.

Thanks for the tip pal

no need to get snotty. there are a lot of people who read these boards for help and tips and take away formulas and tricks without understanding the concepts or exceptions to the rule or investigating; I think it is important to note them.

I have seen people using this formula and I didn't understand where it came from and no one really explained it so I started playing with it (it is what people should do with a new concept) and I quickly noted the exception and proper use.