# Partitions with no 1s

\begin{align} p(17) &= 297 \\ p(18) &= 385 \\ p(19) &= 490 \\ p(20) &= 627 \\ p(21) &= 792 \end{align}

Let $$p(n)$$ be the number of partitions of an integer $$n$$. The values of $$p(17), p(18),p(19),p(20), p(21)$$ are as shown above.

How many partitions of 20 are there that do not contain any parts equal to 1?

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