# Shouldn't I Post This In July?

$$28$$ random draws are made from the set $$\{1,2,3,4,5,6,7,8,9,A,B,C,D,J,K,L,U,X,Y,Z\}$$ containing $$20$$ elements.

Let $$P$$ be the probability that the sequence

$$CUBAJULY1987$$

occurs in that order in the chosen sequence. If $$P$$ can be expressed as $$\frac {a\times b^c-d\times b^e}{b^f}$$, find $$a+b+c+d+e+f$$.

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