Question 1059672
{{{a[n]=a[1]+(n-1)*d}}}
{{{a[n]=0+(n-1)*(1/3)}}}
{{{a[n]=(1/3)n-1/3}}}
{{{a[n]=(1/3)(n-1)}}}
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{{{a[20]=(1/3)(20-1)}}}
{{{a[20]=19/3}}}