364、 12 1、40、 13、(4)、( 1)

(364 =121* 3+1,12/= 40 * 3+1,and so on)

2. 1、 1、3、4、7、9、 15、 16、3 1、25、(63)、(36)、

Take the sequence apart.

The odd term is 3 7 15 3 1, and the last number = the previous number ×2+ 1.

The even term 4 9 16 25 is the square of (n+ 1).

3.

2*2- 1* 1=(2)+( 1)=3

3*3-2*2=(3)+ (2) =5

1999* 1999- 1998* 1998=( 1999)+( 1998)=(3997)

(solution: A 2-(A- 1) 2 = A+A- 1)

4.

10 50

40 8

There should be many answers to the fourth question. The rule used here is 10*40=50*8. I wonder if the question means this.