Let $p$ be a prime number. Is there a formula for the number of subgroups of 


1. $$\mathbb{Z}/p\mathbb{Z}\times \mathbb{Z}/p^2\mathbb{Z}$$
2. $$\mathbb{Z}/p\mathbb{Z}\times \mathbb{Z}/p\mathbb{Z}\times\mathbb{Z}/p\mathbb{Z}$$


Thanks!



Number of subgroups of a group of orders $p^3$
In the following bachelor thesis:


[On p-groups of low power order](https://people.kth.se/~boij/kandexjobbVT11/Material/pgroups.pdf)


there is a chapter on subgroups, which includes the results you're searching for.


It is an useful work for beginners on p-groups.


