pr -l 63 factorial.lua       >factorial.pr
pr -l 63 fibonacci.lua       >fibonacci.pr
pr -l 63 exponentiation.lua  >exponentiation.pr
pr -l 63 gcd.lua             >gcd.pr
pr -l 63 sqrt.lua            >sqrt.pr
pr -l 63 summation.lua       >summation.pr
pr -l 63 derivative.lua      >derivative.pr
chmod 644 *.lua *.pr