1,1,2,3,5,8,13,21,34,55,89,144

1,1,2,3,5,8,13,21,34,55,89,144

Isn't this Fibonacci sequence? Fibonacci sequence refers to such a sequence: 1, 1, 2, 3, 5, 8, 13, 21 This sequence starts from the third term, and each term is equal to the sum of the first two terms. Its general term formula is: (1 / √ 5) * {[(1 + √ 5) / 2] ^ n - [(1 - √ 5) / 2] ^ n} (also known as "Binet formula

What are the characteristics of 1,2,3,5,8,13,21,34,55,89144?
This is the Fibonacci series

Starting from the third, each is the sum of the first two

1、2、3、5、8、13、21、34、55、89、144…… The characteristics of these numbers
Try to be before 2:00, not too long~

These belong to the Laplacian series
When n (x + 1) = NX + n (x-1) x ＞ 1, n = 1

Why is the sum of 1,1,2,3,5,8,13,21,34,55,89144332 and so on in the middle

1+1=2
1+2=3
2+3=5
3+5=8
5+8=13
8+13=21
13+21=34
21+34=55
34+55=89
5+9=144

How to sum 1 + 3 + 6 + 10 + 15 + 21 + 28 + 36 + n
The nth number is n (n-1) / 2
But how much is the sum?
Be concise, not a series of process, as long as the result!

The first term should be 0, and the nth term is n (n-1) / 2, so the original formula should be 0 + 1 + 3 + 6 + 10 + 15 + 21 + 28 + 36 + +N the result is: and S = (n & # 179; - n) / 6 = n (n-1) (n + 1) / 6N / x09s1 / x0902 / x0913 / x0944 / x09105 / x09206 / x09357 / x09568 / x09849 / x09120 \x09…… n\x09n(n-...

1 3 6 10 15 21 28… Sum up

Man, this is the second-order equal difference, you ask for the first-order, but it's not difficult to find. Lead out the general term and then add it up. Wait a minute, I'll give you a try!

In this paper, we give a group of numbers in order: 1, - 3,5, - 7,9... According to this rule, the number 2013 is
I've made it. There's no need to answer

The square of a is a ^ 2
Let n be an = - (- 1) ^ (n + 1) times (2n-1) = 2013
If 2013 = 2N-1, n = 1007, odd term is positive, even term is negative, so 2013 is the 1007th number

This paper gives a group of numbers arranged in order: 1, - 3,5, - 7,9 According to this rule, the sixth number is (), and the 2013 number is ()

Find the rule first, the positive and negative phases of the queue, and the absolute value is the arithmetic sequence with 2 as the tolerance; therefore, the sixth is - 11, and the 2013 is 4025

Give the number of a column in order: 1, - 3,5, - 7,9, - 11. Continue the following three terms:,,. The number of 2008 in this column is?

13, - 15, 17, the number of 2008 is - 4015

One column number is 1, - 3,5, - 7 What is the sum of the first 2008 numbers in this column?
Explain why

The addition of two terms
1+(-3)=-2
5+(-7)=-2
……
4013+（-4015）=-2
So there are a total of 1004 - 2S
So 1 + (- 3) + 5 + (- 7) + +(-4015)
=1004*(-2)
=-2008