Can an A tag be wrapped in an H1?

Question

Google

<h1>
    <a></a>
</h1>

As far as I understand, Google used to take this for spam.
By the way, Google itself does this, on the pages of search results:

<h1><a href="https://www.google.ru/webhp?hl=ru" title="Главная страница Google" id="logo"><img height="410" src="/images/nav_logo242.png" width="167" alt="Google" onload="google.aft&amp;&amp;google.aft(this)"></a></h1>

Answer 1

Google can't take it for spam, Google defines spam by other means.

By the way, Google itself does this, on the pages of search results:

well yes. Why not? Read the HTML standard before asking stupid questions.

Answer 2

What's stopping you from doing the opposite? add H1 to tag A

Answer 3

Well, depending on what?
In fact, this is real, systematically it is not correct.
Sometimes you have to do it and you do it.
Why is there a link in h1 ?
h1 is a heading and a link should lead to it, and not vice versa)
In h2, this is still at least somehow justified.