Discuter:Crible d'Ératosthène

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	Crible d'Ératosthène fait partie du projet Mathématiques, qui a pour but d'enrichir le contenu de Wikipédia sur les sujets liés aux mathématiques. Si vous voulez participer, vous pouvez modifier cet article ou visiter la page du projet, où vous pourrez vous joindre au projet et consulter la liste des tâches et des objectifs. Le portail Mathématiques pourrait aussi vous intéresser.
B	Cet article a été classé comme d'Avancement B selon le Tableau d'évaluation du projet. (Voir les statistiques)
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Bonjour,

La table a été construite avec un programme en perl dont voici le source : Pour l'utiliser tapper en ligne de commande :

perl crible.pl > prem.html

et éditer le fichier obtenu pour supprimer le </tr> du début.

Ce n'est pas la perfection.

COLETTE 21:20 mar 29, 2003 (CET)

#!/usr/bin/perl

$N=500;

for ($i=0; $i<$N; $i++) {
    $a[$i]=1;
    $c[$i]=0;
}

$a[0]=0;
$a[1]=0;
$i=2;
$k=0;
while ($i<=$N)  {
    $paspremier=1;
    while ($paspremier && ($i<=$N)) {
        $paspremier=($a[$i]==0);
        $i++;
    }
    $i--;
    $k++;
    $c[$i]=$k;
    $j=2;
    while ($j*$i<=$N) {
        if ($a[$i*$j]==1)
        {
            $c[$i*$j]=$k;
        }
        $a[$i*$j]=0;
        $j++;
    }
    $i++;
}

@cou=("yellow", "\"#0000ff\"", "\"#ff0000\"", "\"#deff7d\"", "\"#de7fff\"", "\"#1571ff\"", "\"#15ff8c\"", "\"#92ba8c\"", "\"#92008c\"", "\"#b04f6f\"", "\"#b04fe6\"", "\"#b0ffe6\"", "\"#1f99d5\"", "\"#ad26d5\"", "\"#deabd5\"", "\"#1fffff\"", "\"#ffff23\"", "\"#ffe09d\"", "\"#f9cdff\"", "\"#f9cd15\"", "\"#5affbc\"",
"\"#7f7fe2\"", "\"#51964f\"", "\"#ff9782\"", "\"#0077c0\"", "\"#00cbcb\"", "\"#8c38cb\"", "\"#d5aecb\"", "\"#d5ae4f\"", "\"#00d9ff\"", "\"#a59758\"",  "\"#ffc6c7\"", "\"#ffc0c0\"",
"yellow", "\"#0000ff\"", "\"#ff0000\"", "\"#deff7d\"", "\"#de7fff\"", "\"#1571ff\"", "\"#15ff8c\"", "\"#92ba8c\"", "\"#92008c\"", "\"#b04f6f\"", "\"#b04fe6\"", "\"#b0ffe6\"", "\"#1f99d5\"", "\"#ad26d5\"", "\"#deabd5\"", "\"#1fffff\"", "\"#ffff23\"", "\"#ffe09d\"", "\"#f9cdff\"", "\"#f9cd15\"", "\"#5affbc\"",
"\"#7f7fe2\"", "\"#51964f\"", "\"#ff9782\"", "\"#0077c0\"", "\"#00cbcb\"", "\"#8c38cb\"", "\"#d5aecb\"", "\"#d5ae4f\"", "\"#00d9ff\"", "\"#a59758\"",  "\"#ffc6c7\"", "\"#ffc0c0\"",
"yellow", "\"#0000ff\"", "\"#ff0000\"", "\"#deff7d\"", "\"#de7fff\"", "\"#1571ff\"", "\"#15ff8c\"", "\"#92ba8c\"", "\"#92008c\"", "\"#b04f6f\"", "\"#b04fe6\"", "\"#b0ffe6\"", "\"#1f99d5\"", "\"#ad26d5\"", "\"#deabd5\"", "\"#1fffff\"", "\"#ffff23\"", "\"#ffe09d\"", "\"#f9cdff\"", "\"#f9cd15\"", "\"#5affbc\"",
"\"#7f7fe2\"", "\"#51964f\"", "\"#ff9782\"", "\"#0077c0\"", "\"#00cbcb\"", "\"#8c38cb\"", "\"#d5aecb\"", "\"#d5ae4f\"", "\"#00d9ff\"", "\"#a59758\"",  "\"#ffc6c7\"", "\"#ffc0c0\"",
"yellow", "\"#0000ff\"", "\"#ff0000\"", "\"#deff7d\"", "\"#de7fff\"", "\"#1571ff\"", "\"#15ff8c\"", "\"#92ba8c\"", "\"#92008c\"", "\"#b04f6f\"", "\"#b04fe6\"", "\"#b0ffe6\"", "\"#1f99d5\"", "\"#ad26d5\"", "\"#deabd5\"", "\"#1fffff\"", "\"#ffff23\"", "\"#ffe09d\"", "\"#f9cdff\"", "\"#f9cd15\"", "\"#5affbc\"",
"\"#7f7fe2\"", "\"#51964f\"", "\"#ff9782\"", "\"#0077c0\"", "\"#00cbcb\"", "\"#8c38cb\"", "\"#d5aecb\"", "\"#d5ae4f\"", "\"#00d9ff\"", "\"#a59758\"",  "\"#ffc6c7\"", "\"#ffc0c0\"",
"yellow", "\"#0000ff\"", "\"#ff0000\"", "\"#deff7d\"", "\"#de7fff\"", "\"#1571ff\"", "\"#15ff8c\"", "\"#92ba8c\"", "\"#92008c\"", "\"#b04f6f\"", "\"#b04fe6\"", "\"#b0ffe6\"", "\"#1f99d5\"", "\"#ad26d5\"", "\"#deabd5\"", "\"#1fffff\"", "\"#ffff23\"", "\"#ffe09d\"", "\"#f9cdff\"", "\"#f9cd15\"", "\"#5affbc\"",
"\"#7f7fe2\"", "\"#51964f\"", "\"#ff9782\"", "\"#0077c0\"", "\"#00cbcb\"", "\"#8c38cb\"", "\"#d5aecb\"", "\"#d5ae4f\"", "\"#00d9ff\"", "\"#a59758\"",  "\"#ffc6c7\"", "\"#ffc0c0\"");

print "<table border=\"1\" cellspacing=\"0\" cellpadding=\"2\">";

$j=0;
for ($i=0; $i<$N; $i++) {
    if ($i % 20==0) {
        $b[$j++]="</tr>\n";
        $b[$j++]="<tr>";
    }
    if ($a[$i]!=0) {
        $b[$j++]="<td bgcolor=$cou[$c[$i]]>";
        $b[$j++]=$i;
        $b[$j++]="</td>";
    }
    else {
        $b[$j++]="<td><font color=$cou[$c[$i]]><strike>";
        $b[$j++]=$i;
        $b[$j++]="</strike></font></td>";
    }
}



print "@b";

print "</table>";