# Compositions with no 1

A composition of $$n$$ is an expression of $$n$$ as a sum of not necessarily distinct positive integers, where the order matters. Note that $$n = n$$ counts as a composition of $$n$$.

Let $$C_n$$ be the number of compositions of $$n$$ with no part equal to 1.

For instance, $$C_6 = 5$$ because $$6 = 6 =4+2=3+3=2+4=2+2+2.$$

Find $$C_{15}$$.

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