【Analysis】Find the pattern
The sums are $2,3,5,8,13,21,34,55,89,144,233,377,610 ; \ldots .$. (Notice that each subsequent number is the sum of the previous two)
The thirteenth sum is 610.
12. Arrange the numbers of Pascal's Triangle aligned to the far left as follows:

The numbers in the diagonal direction connected by arrows are referred to as a diagonal, for example, the first diagonal is “ $1 \leftarrow 1$ ”, the second diagonal is “ $1 \longleftrightarrow \rightarrow 2$ ”, and the third diagonal is “ $1 \longleftrightarrow 3 \longleftrightarrow \rightarrow 1$ ”.
What is the sum of all the numbers on the 13th diagonal?