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Assume the cylinders are released from rest. In each case, “there is friction” is interpreted as sufficient <static friction> for <rolling without slipping> at the rough contacts. Without a coefficient or a no-slip assumption, sliding cases would not have a unique specified acceleration. On release the two lower cylinders separate; their mutual contact must not be retained as a rigid constraint.
Let the top cylinder's initial downward <acceleration> be $w$, and each lower cylinder's outward horizontal <acceleration> be $u$. The top cylinder initially has no horizontal <acceleration>. Differentiating the fixed upper-to-lower centre separation twice at the initial zero <velocity> gives
$$
\boxed{u=\sqrt3\,w.}
$$
By reflection symmetry the top cylinder has zero <angular acceleration>, while the lower cylinders rotate in opposite senses.
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