: doit ( -- )
CONSTANT: nums {
    { 13 0 }
    { 41 3 }
    { 23 21 }
    { 19 32 }
    { 29 42 }
    { 37 50 }
    { 17 61 }
}

481551 [
  617143 +  
  dup nums [
    first2 13 -
    swap [ + ] dip mod zero? not
  ] with find nip not
  not
] loop
13 - .
;
! Running time: 25.044066321 seconds
doit