// Solver for "Gelfand'sQuestion" // http://mathworld.wolfram.com/GelfandsQuestion.html n=1 a = new array while true { a@0 = left[toString[2^n], 1] a@1 = left[toString[3^n], 1] a@2 = left[toString[4^n], 1] a@3 = left[toString[5^n], 1] a@4 = left[toString[6^n], 1] a@5 = left[toString[7^n], 1] a@6 = left[toString[8^n], 1] a@7 = left[toString[9^n], 1] j = join["", a] if j == "23456789" println["**** $n $j"] if length[toSet[a]] == 1 println["**** $n $j"] n = n + 1 if n mod 10000 == 0 println[n] }