Because the first line has 1, is it 2? a；

There are two numbers in the second line. Is it 2? a；

There are four numbers in the third line. Is it 2? a；

There are eight numbers in the fourth line. Is it 2? a；

So the number of the nth row is the second power of n- 1.

Because the first line is 1, it is 2? - 1;

The first number in the second line is 3. Is it 2? - 1;

The first number in the third line is 7, which means 2? - 1;

So the first number in the nth row is 2- 1 n power; The n in the nth row is: 2 to the n power-1+2 (n- 1 = 2 to the n power +2n-3.