%!PS

/apush { % [a b] c -> [a b c]
    /t exch def
    [ exch aload pop t ]
} bind def

/is_prime {
    currentdict /ret undef
    /n exch def
    n 2 gt n 2 mod 0 eq and {
        /ret false def
    } if
    n 3 gt n 3 mod 0 eq and {
        /ret false def
    } if
    currentdict /ret known not {
        /lim n sqrt cvi def
        /k6 0 def
        {
            /k6 k6 6 add def
            [ k6 1 sub k6 1 add ] {
                /t exch def
                t lim le {
                    n t mod 0 eq {
                        /ret false def
                        exit
                    } if
                } {
                    /ret true def
                    exit
                } ifelse
            } forall
            currentdict /ret known {
                exit
            } if
        } loop
    } if
    ret
} bind def

/longprime {
    /nn exch def
    /o 0 array def
    /b 5 def
    {
        /b b 2 add def
        b is_prime {
            /k 1 def
            /l 0 def
            {
                /k k 10 mul def
                /l l 1 add def
                /k k b mod def
                k 1 eq {
                    exit
                } if
            } loop
            l b 1 sub eq {
                /o o b apush def
                /nn nn 1 sub def
            } if
        } if
        nn 0 le {
            exit
        } if
    } loop
    o
} bind def

5 longprime ==

60 longprime ==