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Ten-digit codes that fall then rise

Question

A ten-digit code ABCDEFGHIJABCDEFGHIJ uses each digit 00 through 99 exactly once. The digits must strictly decrease from AA to EE (A>B>C>D>EA>B>C>D>E) and then strictly increase from EE to JJ (E<F<G<H<I<JE<F<G<H<I<J). How many such codes are there?

Short answer

126126. EE is below every other digit, so E=0E=0. Choosing which 4 of the remaining 9 digits go before it fixes the whole code, since each side has only one valid order. That gives (94)=126\binom94=126.

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