\newcount\a \newcount\b \newcount\c \newcount\n \newcount\p \newcount\q \def\div#1:#2:#3:{% \ifnum#1>#2 % \advance#1 by-#2 % \div#1:#2:#3:% \else% \ifnum#1=#2 % #3=1% \else% #3=0% \fi% \fi% } \long\def\isprime#1:#2:#3:{% #3=0% \ifnum#1>#2 % \a=#1 % \div\a:#2:\c: % \ifnum\c=0 % \b=#2 % \advance\b by 1 % \isprime#1:\the\b:#3:% \else #1\par% \fi% \else% #3=1% \fi% } \def\listprimes#1:#2:#3:#4:{% \isprime\the#1:2:#4: % \ifnum#4=0 % \advance#2 by 1 % \fi \ifnum#2<#3 % \advance#1 by 1 % \listprimes#1:#2:#3:#4: % \fi } \listprimes\p:\n:11:\q: \end