Question 1205679
the nth term of a sequence is denoted by {{{3n(2n-1)}}}

 find the sum of the first {{{5}}} terms using {{{n}}} values from {{{1}}} to {{{5}}}

1st term is {{{3*1(2*1-1)=3}}}
2nd term is {{{3*2(2*2-1)=18}}}
3rd term is {{{3*3(2*3-1)=45}}}
4th term is {{{3*4(2*4-1)=84}}}
5th term is {{{3*5(2*5-1)=135}}}

the sum is {{{3+18+45+84+135=285}}}