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Aanchal Malhotra (100)

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Hey guys....

Its time for teasing your brains a bit and answer the question...

Here is a series of numbers. What is the next number in the sequence?
1
11
21
1211
111221
312211
13112221

Lets see what you come up with

    
Harvish K. Sonar (0)

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1.

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Priyank Kumar (49)

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INDUCTION IS IMPOSSIBLE
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Abhishek Gorai (15)

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??? How to do ??? Don't see any pattern
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muni mohith reddy (0)

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1 is the answer
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omkar kishor waghe (0)

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3.

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G N Giridhar Sanjay (65)

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1113213211
The first row - 1 - contains one 1 -> 11
11 contains two 1's -> 21
21 contains one 2, one 1 ->1211
1211 contains one 1, one 2, two 1's ->111221
etcetera.
Building on that theory, it would go

111221 contains three 1's, two 2's, one 1-> 312211
312211 contains one 3,one 1,two 2's two 1's->13112221
13112221 contains one 1,one 3,three 2's, one 1,

therefore the next sequence of numbers would be ->1113213211



If you think you cannot solve a question,then don't try it because you can't solve it
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Aakanksha Sangwan (55)

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1 ?
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Bhargavaram (0)

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1
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1
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Rajat1196 (45)

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I think 1.....

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boywholived (450)

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 I will tell you what this is 

first just write 1
now read (You can see a single(one) one)
Hence read one one
and write it . Now you get 
11
Now again read
there are two(ones) hence say two 1
write
21
Now read
one two one 1
1211
now read 
111221
go onnn continuing....... You wiil get this 
pLEASE CLICK LIKE

A small history of this sequence
This sequence is called asA005150
 

A005150 as a simple table

n   a(n)
1   1
2   11
3   21
4   1211
5   111221
6   312211
7   13112221
8   1113213211
9   31131211131221
10   13211311123113112211
11   11131221133112132113212221
12   3113112221232112111312211312113211

[1,11,21,1211,111221,312211,13112221,1113213211, 31131211131221,13211311123113112211, 11131221133112132113212221, 3113112221232112111312211312113211]

 

 

Look and Say Sequence

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The integer sequence beginning with a single digit in which the next term is obtained by describing the previous term. Starting with 1, the sequence would be defined by "1, one 1, two 1s, one 2 one 1," etc., and the result is 1, 11, 21, 1211, 111221, .... Similarly, starting the sequence instead with the digit d for 2<=d<=9 gives d, 1d, 111d, 311d, 13211d, 111312211d, 31131122211d, 1321132132211d, ..., as summarized in the following table.

d Sloane sequence
1 A005150 1, 11, 21, 1211, 111221, 312211, 13112221, 1113213211, ...
2 A006751 2, 12, 1112, 3112, 132112, 1113122112, 311311222112, ...
3 A006715 3, 13, 1113, 3113, 132113, 1113122113, 311311222113, ...
LookAndSaySequenceDigits

The number of digits in the nth term of the sequence for d=1 are 1, 2, 2, 4, 6, 6, 8, 10, 14, 20, 26, 34, 46, 62, ... (Sloane's A005341). Similarly, the numbers of digits for the nth term of the sequence for d=2, 3, ..., are 1, 2, 4, 4, 6, 10, 12, 14, 22, 26, ... (Sloane's A022471). These sequences are asymptotic to Clambda^n, where

C_1  approx 1.567...
(1)
C_d  approx 1.814...
(2)
lambda = 1.303577269034296....
(3)
LookAndSaySequenceRoots

The quantity lambda is known as Conway's constant (Sloane's A014715), and amazingly is given by the unique positive real root of the polynomial

 0=x^(71)-x^(69)-2x^(68)-x^(67)+2x^(66)+2x^(65)+x^(64)-x^(63)-x^(62)-x^(61)-x^(60)-x^(59)+2x^(58)+5x^(57)+3x^(56)-2x^(55)-10x^(54)-3x^(53)-2x^(52)+6x^(51)+6x^(50)+x^(49)+9x^(48)-3x^(47)-7x^(46)-8x^(45)-8x^(44)+10x^(43)+6x^(42)+8x^(41)-5x^(40)-12x^(39)+7x^(38)-7x^(37)+7x^(36)+x^(35)-3x^(34)+10x^(33)+x^(32)-6x^(31)-2x^(30)-10x^(29)-3x^(28)+2x^(27)+9x^(26)-3x^(25)+14x^(24)-8x^(23)-7x^(21)+9x^(20)-3x^(19)-4x^(18)-10x^(17)-7x^(16)+12x^(15)+7x^(14)+2x^(13)-12x^(12)-4x^(11)-2x^(10)-5x^9+x^7-7x^6+7x^5-4x^4+12x^3-6x^2+3x-6,
(4)

all of whose roots are illustrated above.

In fact, the constant is even more general than this, applying to all starting sequences (i.e., even those starting with arbitrary starting digits), with the exception of 22, a result which follows from the cosmological theorem. Conway discovered that strings sometimes factor as a concatenation of two strings whose descendants never interfere with one another. A string with no nontrivial splittings is called an "element," and other strings are called "compounds." It is postulated that every string of 1s, 2s, and 3s that does not contain four of the same number in succession eventually "decays" into a compound of 92 special elements, named after the chemical elements.

 


Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
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boywholived (450)

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are everybody okk with my solution
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