#!/bin/bash min=4611686018427387904 max=$((min + 20000)) PRIMESIEVE="/export/documents/info/is1+2/asr/primesieve" $PRIMESIEVE $min -n 20000 > primes.txt while read q; do echo "chargement" p=$((2*q + 1)) if $PRIMESIEVE $p -n 1 | grep -q "^$p$"; then echo "$p" fi done < primes.txt