# I am perplexed

Let $$N$$ be a $$2n$$ digit number with digits $$d_{1},d_{2},d_{3},...,d_{2n}$$ from left to right $$i.e$$ $$N= \overline {d_{1}d_{2}....d_{2n}}$$ where $$d_{p}$$ is not equal to $$0$$ , $$p=1,2,...,2n$$. Find the number of such $$N$$ so that the sum $\sum_{q=1}^{n}d_{2q-1} \times d_{2q}=even$ for $$n=7$$ .

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