Answer
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Work Step by Step
STEP 1
Writing finite or infinite sum of those number which follow some regularity in shortest form is sigma notation
STEP 2
the number upon $\Sigma$ is last value of n . the number below $\Sigma$ i s first value of n. and it the right the formula of terms are given
CONCLUSION
Sigma is a minimized method for composing an amount of numbers that keep a specific rule.
