= Solution
Use the neutral-fragment skeletal count: each AlMe supplies two electrons, each CEt supplies three and the bridging H supplies one. Hence
$$
\boxed{N_{\rm skeletal}=8(2)+5(3)+1=32=16\text{ pairs}.}
$$
There are \b[13 nonhydrogen skeletal vertices], eight Al plus five C, and $16=n+3$ pairs. In the usual PSEP classification this is therefore \b[arachno], corresponding to a 15-vertex closo parent with two vertices absent. The μ$_4$-H cap contributes an electron but is not counted as a carbon-like skeletal vertex. The aluminium cube is a convenient subframework; its eight corners alone are not the complete Wade skeleton. Calculations on capped cubic carbaalanes likewise identify 16 skeletal pairs for the five-carbon-cap/one-hydride-cap case.<Electron Counting in Carbaalane Clusters with Cubic Aluminum Core by Benoit Creton and others>[2007, five conical carbon caps and one hydride cap]{ref}
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