default Optional<T> childAtPath(final int... path) {
		return childAtPath(Path.of(path));
	}
Return the child node at the given {@code path}. A path consists of the
child index at a give level, starting with level 1. (The root note has
level zero.) {@code tree.childAtPath(2)} will return the third child node
of {@code this} node, if it exists and {@code tree.childAtPath(2, 0)} will
return the first child of the third child of {@code this node}.

@since 4.3

@see #childAtPath(Path)

@param path the child path
@return the child node at the given {@code path}
@throws NullPointerException if the given {@code path} array is
        {@code null}
@throws IllegalArgumentException if one of the path elements is smaller
        than zero
jenetics.ext/src/main/java/io/jenetics/ext/util/Tree.java