1. Arrange the natural numbers as shown in the figure below. In this arrangement, the number 9 is in the third place and the second column? 1 2 4 7 11 16... 3 5 8 12 17... 6 9 13 18... 10 14 19... 15 20... 21... ... 2. There is a new operation *, which is defined as 1 2 x＊y=---+ ----------- x+y （x=1)(y+a) one Known 5 * 2=--- 9, 3 * 2 3. # denotes a new operation symbol. It is known that 2 # 3 = 2 + 3 + 4, 6 # 2 = 6 + 7, 3 # 5 = 3 + 4 + 5 + 6 + 7. According to this rule, n # 8 = 228, what is n? 4. For any two natural numbers a and B, a # B = a (a + 1) (a + 2). (a + B-1), if (x # 3) # 2 = 3660, find X 5. Let m and n be natural numbers, am denote the sum of the digits of M, an denote the sum of the digits of N, and m * n denote the remainder of M divided by N. given that the sum of M and N is 8088, find the value of (am + an) * 9 You can answer as many questions as you can

1. Arrange the natural numbers as shown in the figure below. In this arrangement, the number 9 is in the third place and the second column? 1 2 4 7 11 16... 3 5 8 12 17... 6 9 13 18... 10 14 19... 15 20... 21... ... 2. There is a new operation *, which is defined as 1 2 x＊y=---+ ----------- x+y （x=1)(y+a) one Known 5 * 2=--- 9, 3 * 2 3. # denotes a new operation symbol. It is known that 2 # 3 = 2 + 3 + 4, 6 # 2 = 6 + 7, 3 # 5 = 3 + 4 + 5 + 6 + 7. According to this rule, n # 8 = 228, what is n? 4. For any two natural numbers a and B, a # B = a (a + 1) (a + 2). (a + B-1), if (x # 3) # 2 = 3660, find X 5. Let m and n be natural numbers, am denote the sum of the digits of M, an denote the sum of the digits of N, and m * n denote the remainder of M divided by N. given that the sum of M and N is 8088, find the value of (am + an) * 9 You can answer as many questions as you can

1. Arrange the natural numbers as shown in the figure below. In this arrangement, the number 9 is in the third place and the second column?
1 2 4 7 11 16...
3 5 8 12 17...
6 9 13 18...
10 14 19...
15 20...
21...
The first 1 * (1 + 1) / 2 = 1 in the first column
The second 2 * (2 + 1) / 2 = 3 in the first column
The third 3 * (3 + 1) / 2 = 6 in the first column
The fourth 4 * (4 + 1) / 2 = 10 in the first column
.
Because 62 * 63 / 2 = 1953 63 * 64 / 2 = 2016 1953