Question 1121366
{{{system(48, 48*r, 48*r^2, 384)}}}


{{{48*r^3=384}}}

{{{r^3=384/48}}}

{{{r=2}}}

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First six terms:   <pre>6, 12, 24, 48, 96, 192</pre>

There is a formula for their sum if you want.
sum:   378