• Taxicab(n) exists (Hardy and Wright, 1938)
  • Taxicab(5) (Wilson, 1997) 48988659276962496 = 3878733 + 36575733 = 10783933 + 36275333 = 20529233 + 34295233 = 2142433 + 33658833 = 23151833 + 33195433
  • Taxicab(6)? 99% probability = 24153319581254312065344 (Rathbun, 2002; Calude, Calude and Dinneen, 2003)
  • Are there any numbers that are a sum of two fifth powers in two ways?