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Guy, Unsolved Problems In Number Theory, 3rd edition, A12 (page 45) says "Selfridge, Wagstaff & Pomerance offer 500.00 + 100.00 + 20.00 for a composite $n\equiv3{\rm\ or\ }7\pmod{10}$ which divides both $2^n-2$ and the Fibonacci number $u_{n+1}$ or 20.00 + 100.00 + 500.00 for a proof that there is no such $n$." John Selfridge having left us, I do not know whether his part of the offer still applies.