Tool to generate Conway sequences. The Conway Sequence is a sequence of digits (also called Look-and-Say sequence) invented by mathematician John H. Conway. Each term is made of the reading of the digits (the number of consecutive digits) of the previous term.

Conway Sequence - dCode

Tag(s) : Mathematics,Fun

dCode is free and its tools are a valuable help in games, puzzles and problems to solve every day!

You have a problem, an idea for a project, a specific need and dCode can not (yet) help you? You need custom development? *Contact-me*!

This page is using the new English version of dCode, *please make comments* !

Sponsored ads

Tool to generate Conway sequences. The Conway Sequence is a sequence of digits (also called Look-and-Say sequence) invented by mathematician John H. Conway. Each term is made of the reading of the digits (the number of consecutive digits) of the previous term.

To generate the next term in the sequence, it must use the previous one, read it digit by digit and locate the numbers that are repeated consecutively. The sequence usually begins with 1 first term (also called seed).

1 reads a 1 is 11

11 reads as two 1 or 21

21 reads as one 2 and one 1 so 1211

1211 reads one 1, one 2 and two 1 so 111221

111221 is three 1, two 2 and one 1 is 312211 and so on..

The Conway sequence is 1, 11, 21, 1211, 111221, 312211, 13112221, 1113213211, ...`

The Conway sequence is set to begin with 1 by default, but it is possible to consider a different seed.

For a seed g of 2,3,4,5,6,7,8,9 or 0, these values are obtained:

g, 1g, 111g, 311g, 13211g, 111312211g ... (the seed is always at the end).

It is possible to use slightly different rules:

- Read the previous term and count all occurrences of numbers, listed in ascending order.

1, 11, 21, 1112, 3112, 211213, 312213, 212223, 114213, 31121314, 41122314, ...

- Read the previous term and count all occurrences of numbers, listed in descending order.

1, 11, 21, 1211, 1231, 131221, 132231, 232221, 134211, 14131231, 14231241, ...

- Read the previous term and count all occurrences of numbers, listed in order of appearance.

1, 11, 21, 1211, 3112, 132112, 311322, 232122, 421311, 14123113 ...

The Conway sequence is similar to run-length encoding.

`// Yves PRATTER`

// Version 1.0 - 2011/11/07

function previousConway(t) {

r = "";

// impossible

if (t.length%2 == 1) return r;

idx = 0;

while (idx < t.length){

for(i=0; i < t.charAt(idx); i++) { r += t.charAt(idx+1); }

idx += 2;

}

return r;

}

function conway(t) {

if (t == "") return "0";

r = "";

idx = 0;

while (idx < t.length){

for(i=1; t.charAt(idx+i) == t.charAt(idx); i++) {}

r += i + t.charAt(idx);

idx += i;

}

return r;

}

dCode retains ownership of the source code of the script Conway Sequence. Except explicit open source licence (free / freeware), any algorithm, applet, software (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, translator), or any snippet or function (convert, solve, decrypt, encrypt, decipher, cipher, decode, code, translate) written in PHP (or Java, C#, Python, Javascript, etc.) which dCode owns rights can be transferred after sales quote. So if you need to download the Conway Sequence script for offline use, for you, your company or association, see you on contact page !

sequence,conway,look,say,audioactive,11,21,1211,111221,312211,13112221,1113213211

Source : http://www.dcode.fr/conway-sequence

© 2016 dCode — The ultimate 'toolkit' website to solve every problem. dCode