A topic for finding rules: 2,8,5,20,7,28,11,44, (), 12

2,8,5,20,7,28,11,44, (3), 12. The law is 2x4 = 8,5x4 = 20,7x4 = 28,11x4 = 44, (3) X4 = 12,

2, 8, 5, 20, 7, 28, 11, 44______ ，12．

From the analysis, it is concluded that: because 12 △ 4 = 3, it is concluded that:
2，8，5，20，7，28，11，44，3，12．
So the answer is: 3

Fill in the numbers 2,3,5,7,11, (), 17,19

Thirteen

Fill in the numbers 1,5,9,13,17,21_ 1 / 2, 2 / 3, 5 / 8, 8 / 13_ 16 of 12, 25 of 21, 36 of 32_ ,___

1,5,9,13,17,21,25
1 in 2, 2 in 3, 3 in 5, 5 in 8, 8 in 13, 13 in 13 and 13 in 21
9 in 5, 16 in 12, 25 in 21, 36 in 32, 49 in 45, 64 in 60

Fill in the numbers 1, 6, 4, 8, 7, 10, () () () 13, 14 urgently!

First, third, Fifth The bits are: 1, 4, 7 (1 start + 3)
Second, fourth, sixth The bits are: 6, 8, 10 (6 start + 2)
So fill in 10, 12

Fill in the numbers: 1, 1 / 8, 1 / 27, (), ()

1. 1 / 8, 1 / 27, (1 / 64) and (1 / 125)
1 = 1 / 3 of 1
1 / 8 = 1 / 3 of 2
1 / 27 = 1 / 3 cube
…………

1, 2, 3, negative 4, 5, 6, 7, 8. What are the 99 and 2013 numbers of this column

1,2,3,-4,5,6,-7,-8,9,-10,-11,-12,-13,-14,-15,-16,-17,-18,-19,20,-21,-22,23,24,-25,26,27,28,29,30,31,32,
32 numbers a cycle,
99 = 3 * 32 + 3, so the number of 99 is 99
2013 = 62 * 32 + 29, so the number of 2013 is 2013

1 + 2-3-4 + 5 + 6-7-8 + 9 + 10 -..., which is a continuous integer starting from 1, two take positive, two take negative write down, then what is the sum of the first 2013 numbers

1+2-3-4+5+6-7-8+9+10-...
The sum of two positive and two negative is - 4
2013÷4=503..1
-4×503+2013=2013-2012=1

3, - 6,9, - 12,..., 2013, - 2016

The 100th is negative
=3+(n-1)3=300
So it's - 300
The sum of the column numbers is
3,9,15,...2013
-6,-12,-18,...-2016
=-3*(（2016-3)/3+1)/2=-3*336=-1008

Given the number of a column arranged according to a certain rule: 1, √ 2, √ 3,2, √ 5, √ 6, √ 7 Given the number of a column arranged according to a certain rule: 1,√2,-√3,2,√5,-√6,√7,... (1) Observe the number of columns and tell a rule of arrangement (2) If you want to start with at least 5 consecutive numbers, please start with a number of them

Then, two negative numbers in succession
In addition to the sign, the square roots of positive integers are in turn
1 + √ 2 - √ 3 + 2 + √ 5 is about 4.9, which is not enough
1+√2-√3+2+√5-√6+√7>5
So at least seven

A topic for finding rules: 2,8,5,20,7,28,11,44, (), 12