# A Pre-RMO question! -22

Probability Level 1

If the number of subsets of $\{ 1,2,3,4,5,6,7,8,9 \}$ that are subsets of neither $\{ 1,2,3,4,5 \}$ nor $\{ 4,5,6,7,8,9 \}$ is $k$, find the sum of the digits of $k$.

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