2. (6 points) Arrange some small circles with the same radius according to the pattern shown in the figure: the 1st figure has 6 small circles, the 2nd figure has 10 small circles, the 3rd figure has 16 small circles, the 4th figure has 24 small circles, $\cdots$, following this pattern, the 6th figure has $\qquad$ small circles.
【Analysis】According to the problem, the number of small dots at the four corners of each shape is 4. In the 1st shape, the number of small circles is 6, which can be written as $6=1 \times(1+1)+4$; in the 2nd shape, the number of small circles is 10, which can be written as $10=2 \times(2+1)+4$; in the 3rd shape, the number of small circles is 16, which can be written as $16=3 \times(3+1)+4$; in the 4th shape, the number of small circles is 24, which can be written as $24=4 \times(4+1)+4 ; \cdots$ Therefore, for the $n$th shape, the number of small dots can be written as: $n \times(n+1)+4$, from which the problem can be solved.

【Solution】According to the analysis of the problem, the number of small circles in the $n$th shape is $n \times(n+1)+4$. When $n=6$,

the number of small circles in the shape is: $6 \times 7+4=46$ (circles).
Answer: The number of small dots in the 6th shape is 46.
Therefore, the answer is: 46.