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Dominating Numbers

 Published on Saturday, 5th March 2022, 04:00 pm and solved by 1843
Difficulty: Level 6 [17%]

Problem 788

A dominating number is a positive integer that has more than half of its digits equal.

For example, $2022$ is a dominating number because three of its four digits are equal to $2$. But $2021$ is not a dominating number.

Let $D(N)$ be how many dominating numbers are less than $10^N$. For example, $D(4) = 603$ and $D(10) = 21893256$.

Find $D(2022)$. Give your answer modulo $1\,000\,000\,007$.



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