MathDB

A natural number is called a prime power if that number can be expressed as

p^n

for some prime

p

and natural number

n

. Determine the largest possible

n

such that there exists a sequence of prime powers

a_1, a_2, \dots, a_n

such that

a_i = a_{i - 1} + a_{i - 2}

for all

3 \le i \le n

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