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Help with summation problems?
How would you find a formula for the series n, (n-1), (n-2)...1? Thanks!
3 Answers
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- Anonymous10 years agoFavorite Answer
n.(n-1)(n-2)......2.1=n!
- 10 years ago
This is n! -> read n factorial, you multiply the chosen integer by all lower integers until 1.
Ex. 10! = 10*9*8*7*6*5*4*3*2*1 = 3628800
Source(s): Math Student - Anonymous10 years ago
If you're asking for the sum of the series, the formula is sum=n(n+1)/2. You can prove it by mathematical induction.
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