Beats Me

RICHARD Fries of Pimlico chess club sent in this brainteaser to get the grey matter flowing.
What comes next in the sequence: 0 - 2 - 8 - 26 - 80?
This was apparently a question in a test set by University College London (and, no, I did not get the answer).
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242 (each number is the previous number multiplied by 3 and then 2 added)