For $p\in \mathbf{N}$$n\in \mathbf{N}$ is $$p^3 \text{ divides } \sum_{i=1}^{p-1}\binom{p}{i}^2$$$$n^3 \text{ divides } \sum_{i=1}^{n-1}\binom{n}{i}^2=\binom{n}{1}^2+\cdots +\binom{n}{n-1}^2$$ impling $$p \text{ divides } \sum_{i=1}^{p-1}\binom{p}{i}$$$$n \text{ divides } \sum_{i=1}^{n-1}\binom{n}{i}=\binom{n}{1}+\cdots +\binom{n}{n-1}$$?
Notice that the second condition is equvalentequivalent to say: "$p$$n$ is a prime or $p$$n$ is a Poulet number". Or
is $$p^4 \text{ divides } \sum_{i=1}^{p-1}\binom{p}{i}^2$$$$n^4 \text{ divides } \sum_{i=1}^{n-1}\binom{n}{i}^2=\binom{n}{1}^2+\cdots +\binom{n}{n-1}^2$$ impling $$p \text{ divides } \sum_{i=1}^{p-1}\binom{p}{i}$$$$n \text{ divides } \sum_{i=1}^{n-1}\binom{n}{i}=\binom{n}{1}+\cdots +\binom{n}{n-1}$$? Notice that the first condition here is equvalent to say: "$p$$n$ is a Wolstenholme number"