Arrange a group of numbers regularly: 1, - 2, 3, - 4, 5, - 6, 7, - 8, etc (1) What formula do you think can be used to express each of its terms? (2) What is its 100th number (3) Is 2010 the number of this group? If so, what is the number?

RELATED INFORMATIONS

• 1. The natural numbers of 1, 2, 3 and 4. N are grouped according to the following rules: the first group: (1) the second group: (2, 3) the third group; (4, 5, 6) the fourth group: (7, 8, 9)
• 2. Arrange natural numbers according to the following rules. Where is 2009? 1 1 column 2 column 3 column 4 column 1 line 1 2 9 10 2 lines 4 3 8 11 3 lines 5 6 7 12 Four lines 16 15 14 13 5 lines 17 ... There are four options A. Line 17, column 44 B. line 18, column 45 C. line 18, column 46 D. line 19, column 48
• 3. Arrange the natural numbers according to the law 1 2 5 10…… 4 3 6 11…… 9 8 7 12…… 16 15 14 13…… …… …… ………… 1. Find the number of the 10th row from the top and the 13th column from the left 2. Which row should the number 127 start from and which column should it start from the left? 3. Which row should the number 2000 be in and which column should it be from the left? 1 2 5 10…… 4 3 6 11…… 9 8 7 12…… 16 15 14 13…… …… …… …………
• 4. Natural numbers are arranged as follows: one 2 3 4 5 6 7 8 9 …… …… What is the sum of the four numbers (up, down, left and right) adjacent to 2006?
• 5. The natural numbers of 1-299 are arranged as follows 1 2 5 10 17 26 37... 4 3 6 11 18 27 38... 9 8 7 12 19 28 39... Which numbers are 5 and 13? Who and whose numbers are 100? What are the rules?
• 6. Arrange the natural numbers starting from 1 in the following order one 2 3 4 5 6 7 8 9 10 The first number in line n is The last number of N rows is The sum of the numbers in line n is
• 7. Natural numbers are arranged in the following table according to certain rules. What is the fifth book on line 60? one 3 5 7 9 11 13 15 17 …… Want to have the train of thought that solves a problem and calculate formula! Had better say of compare easy to understand
• 8. The first line is 1, the second line is 2, 3, 4, the third line is 5, 6, 7, 8.9, and the fourth line is 10.11.12, 13, 14, 15, 16
• 9. Observe the following table: the first line 1, the second line 1 2 1, the third line 1 2 4 2 1, the fourth line 1 2 4 8 4 2 1 According to the above arrangement rule, the sum of all numbers in the nth row in the sequence table is_________ . First line 1 Second line 1 2 1 The third line 1 2 4 2 1 The fourth line 1 2 4 8 4 2 1
• 10. Arrange the positive integers into the following table according to certain rules: the first line 1, the second line 2 3, the third line 4 5 6, the fourth line 7 8 9 10. What's the 12th in line 2002?
• 11. There is a series of numbers in regular order: - 1,2, - 3,4, - 5,6, - 7,8,... Q: what is the sum of the top 100 items in this series? (to calculate the formula process)
• 12. Please write down the following three numbers directly: (1) 2,4, - 6,8,10, - 12,14, () () （2）2、0、—2、—4、—6、—8、（ ）（ ）（ ） (3) 1. Negative half, two thirds, three quarters, four fifths, five sixths, ()
• 13. 11 7 13 -- 15 12 8 from large to small
• 14. All positive odd numbers are arranged as follows: 1 3 5 7 9 11 13 15 17 19...... find the number in the row 2011 There are N adjacent odd numbers in the nth row. Starting from the second row, the first number in each row and the last number in the previous row are adjacent odd numbers
• 15. Arrange the odd numbers in the following order: 1 5 7 19 3 9 17…… 11 15…… 13…… 3 in the second row and first column; 15 in the third row and second column What's the row and column of 2007
• 16. Pyramid like number order, 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 What is the seventh number on line 200? Because you can't type it, you can make do with it. A comma is a column. I'm in a hurry. If I get it right, I'll get a lot of rewards. The score is a little less, but I can give you something else. First come first served! (by the way, it's better to have a process, but it's better if not.)
• 17. 3 out of 4, 13 out of 16 and 5 out of 6, 11 out of 12, 15 out of 16 and 17 out of 18 in each group
• 18. Put 11 / 12, 17 / 18 and 6 / 5 in descending order
• 19. How to arrange the 9 numbers of 10.11.12.13.14.15.16.17.18 in the same way?
• 20. Press natural numbers by 1, 2, 3 Eight numbers in an unlimited line, and then Press natural numbers by 1, 2, 3 If the sum of the six numbers in the box is 432, what is the sum of the two numbers in the upper left corner and the lower right corner?