MathDB

Let

a_1 < a_2 < .... < a_n < 2n

n

positive integers such that

a_j

does not divide

a_k

j \not= k

. Prove that

a_1 \geq 2^{k}

where

k

is defined by the condition

3^{k} < 2n < 3^{k+1}

and show that it is the best estimate for

a_1

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