\( \definecolor{colordef}{RGB}{249,49,84} \definecolor{colorprop}{RGB}{18,102,241} \)
Given the sequence: \((2,\,6,\,18,\,54,\,162,\,\dots)\), what is its recursive rule?
  • \(u_0=\)
    .
  • \(u_{n+1}=\)