: cr  "\n" . ;      : dip  swap '_ set execute _ ;
: nip  swap drop ;  : last  -1 extract nip ;
: times
    swap iota '_ set
    do   dup 'execute dip _ last 0 == if break then
    loop drop ;

: concat  "" join ;
'* 1 5 "2dup reshape concat . cr 1 +" times