Question 880878
{{{n=1}}},{{{a[1]=(-3)^1=-3}}}
{{{n=2}}},{{{a[2]=(-3)^2=9}}}
{{{n=3}}},{{{a[3]=(-3)^3=-27}}}
{{{n=4}}},{{{a[4]=(-3)^4=81}}}.
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Is your sequence correct?
{{{a[n]=(-3)^n}}}
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Is it {{{a[n]=n*(-3)^n}}}???
If so then,
{{{n=1}}},{{{a[1]=1*(-3)^1=1*-3=-3}}}
{{{n=2}}},{{{a[2]=2*(-3)^2=2*9=18}}}
{{{n=3}}},{{{a[3]=3*(-3)^3=3*-27=-81}}}
{{{n=4}}},{{{a[4]=4*(-3)^4=4*81=324}}}