How do you calculate the summation when the top is n-1? For example, if I want to find the general term of the sequence The first order difference is How do I calculate the sum of k?
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Each term = n^2 - n + 1 ; if n=6, term=31
Same as mine, Krahl; n=6, 1 + 6(5) = 31 ; not a sum
So for ? How do you calculate that? How about ?
What do you mean? The sum of the first n natural numbers is so the sum of the first n-1 natural numbers is and the sum of the first n squared numbers is But these two are different formulae
Originally Posted by Krahl What do you mean? The sum of the first n natural numbers is 1+2+3+...+n=(n)(n+1) so the sum of the first n-1 natural numbers is 1+2+3+...+(n-1)=(n-1)(n-1+1)=(n-1)(n) and the sum of the first n squared numbers is But these two are different formulae The formula you stated for was for , not n-1 EDIT: so if you want to find the sum for n-1, you just substitute n-1 as n into the regular formulas?
yes so just replace n in that formula with n-1.Thats all you need to do. try it out see if it works so it becomes is that ok?
My bad; misread the question... as penance, I'll recite the Hoooooly Rosary twice
Originally Posted by Krahl yes so just replace n in that formula with n-1.Thats all you need to do. try it out see if it works so it becomes is that ok? I understood it at the same time you typed the post! Thank you
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