MathDB

A sequence of real numbers

a_0, a_1, . . .

is said to be good if the following three conditions hold. (i) The value of

a_0

is a positive integer. (ii) For each non-negative integer

i

we have

a_{i+1} = 2a_i + 1

a_{i+1} =\frac{a_i}{a_i + 2}

(iii) There exists a positive integer

k

such that

a_k = 2014

.
Find the smallest positive integer

n

such that there exists a good sequence

a_0, a_1, . . .

of real numbers with the property that

a_n = 2014

.
Proposed by Wang Wei Hua, Hong Kong

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