# Lucas Prime Differences

Level pending

The Lucas Series is defined such $$L_1 = 2, L_2 = 1$$, and for $$i \geq 3$$, $$L_i = L_{i-1} + L_{i-2}$$.

Bill writes down the numbers $$L_1, L_2, \ldots, L_{1400}$$ in order on a (large) sheet of paper. Going through this list, Bill counts the amount of consecutive numbers on his list whose last digit (in base ten) differ by a prime number.

What is Bill's final count?

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