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Seva
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There are countably many polynomials; write them all in a sequence as $P_1,P_2,P_3,...\ $ For every $k\ge 1$, the set $A_k$ of all positive integers which are not the values of any of $P_1,...,P_k$ has a divergent sum of inverses: $\sum_{a\in A_k} 1/a=\infty$. Consequently, we can find pairwise disjoint, finite subsets $A_k'\subset A_k$ such that $\sum_{a\in A_k'} 1/a>1$. Now let $A:=\cup_{k\ge 1} A_k'$. By the construction, the series $\sum_{a\in A}1/a$ diverges, and for each $k$, the image of $P_k$ is disjoint with $A_{k+1}'\cup A_{k+1}'\cup\ldots$; hence, has a finite intersection with $A$.

Does this answer the question, or am I missing something?

Seva
  • 23k
  • 2
  • 59
  • 141