A string of numbers is arranged in the following order: 1,2,3,2,3,4,3,4,4,4,5,6. From the first number on the left, what is the 100th number

Thirty-four
Divide into three series
1,2,3,4...34
2,3,4.34
3,4,5...35
The 100th number is the 34th number in the first sequence, that is, 34

A set of numbers is arranged in the following order: 1,2,3,2,3,4,3,4,4,5,4,5,6. What is the 50th number? What is the law of calculation for such a problem?

It is divided into three groups, and the sequence is composed of 1,2,3...; 2,3,4...; 3,4,5;
50 / 3 = 16 and more than 2, so it is the 16th + 1 = 17 number of the second series, which is 18

A string of numbers is arranged in the following order: 1,2,3,2,3,4. Calculate the sum of the 50th number

If it is divided into three groups, then the beginning of group n is n. because the three numbers are arithmetic sequence and the tolerance is 1, the sum of numbers in group n is 3N + 3,
It is also known that the 50th number belongs to the 17th group. The sum of the numbers in the first 16 groups is 16 (6 + 51) / 2 = 456 (the sum formula of the first n terms of the arithmetic sequence)
Add the first two numbers 17 and 18 of group 17. The result is 491

If a string of numbers is arranged according to the following rule, what is the 50th number? 1,2,3,2,3,4,3,4,4,4,5,4,5,6,

In groups of three
The first in each group is 1 more than the first in the previous group
50 △ 3 = 16 more than 2
The first number in group 17 is 17, then the second number in group 17 is 18, that is, the total number 50 is 18

At 2, 3, 5, 9, 17, 33, 65 The eighth number in this set of regularly arranged numbers is Please tell me the rules

One hundred and twenty-nine
Because the difference between 2 and 3 is 1
The difference between 3 and 5 is 2
The difference between 5 and 9 is 4
The difference between 9 and 17 is 8
The difference between 17 and 33 was 16
33,65, the difference was 32
One times two equals two
Two times two is four
Four times two is eight
Eight times two is 16
16 times 2 is 32
So the eighth number is 65 plus 32 times 2, which is 129

Arrange the odd numbers in the following order 1 5 7 19 21 3 9 17 23 … 11 15 25 … 13 27 … 29 33 … 31 … In this arrangement, the number 17 is in Row 2 and column 3, the number 33 is in row 5 and column 2, and the number 1995 is in Row 2 Line number Column

The analysis shows that 1995 is the number of (1995-1) △ 2 + 1 = 998,
1+2+3+… +When n = 998, n (n + 1) can be obtained
2=998，
Because 44 × (44 + 1) △ 2 = 990, the number in row 1 and column 44 is 990, which is 990 × 2-1 = 1979;
In the first row, the number in column 45 is 1981, in Row 2, column 44 is 1983 By analogy, 1995 is in row 8, column 38
A: the number 1995 is in row 8, column 38
So the answer is: 8.38

1/2 1/5 1/17…… According to this rule, what is the 1990 number Write the rules~~~

Guess ha, I only consider the denominator ① 2 = 2 ^ 0 + 1 ② 5 = 2 ^ 2 + 1 ③ 17 = 2 ^ 4 + 1, so the denominator of item n should be: the (n-2) power of 2 + 1, so the denominator of item 1990 should be: the (1990-2) power of 2 + 1 = 2 ^ 1988 + 1, so the denominator of item 1990 should be: 1 / (2 ^ 1998 + 1)

We know a sequence of regular numbers: 2, 3, 5, 9, 17, 33 , where the 10th number is () A. 512 B. 513 C. 1024 D. 1025

We know a sequence of regular numbers: 2, 3, 5, 9, 17, 33 ,
2=21-1+1
3=22-1+1
5=23-1+1
9=24-1+1
17=25-1+1
33=26-1+1
...
Then, the nth number can be expressed as: 2N-1 + 1
When n = 10, the 10th number is 210-1 + 1 = 513
Therefore, B

Here is a regular set of numbers: 1, 2, 4, 8, 16 , then the number 2005 is () A. 22005 B. 22004 C. 22006 D. 22003

∵1=20，2=21，4=22，…
The number of 2005 is 22004
Therefore, B

There is a regular set of numbers: 1, 2, 4, 16 The 2005 number corresponds to () a. 2's 2005 power B.2's 2005 power - 1 C.2's 2004 power D.2's 2003 power

A string of numbers is arranged in the following order: 1,2,3,2,3,4,3,4,4,4,5,6. From the first number on the left, what is the 100th number