Calculate first term: The series is an arithmetic series where each term is given by the formula 3j. We need to calculate the sum of the first three terms of this series: 3(1)+3(2)+3(3).
Calculate second term: Calculate the first term: 3(1)=3.
Calculate third term: Calculate the second term: 3(2)=6.
Calculate sum of series: Calculate the third term: 3(3)=9.
Calculate sum of series: Calculate the third term: 3(3)=9. Add the three terms together to find the sum of the series: 3+6+9=18.
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