Saturday, September 19, 2009

Euler Project 43


The number, 1406357289, is a 0 to 9 pandigital number because it is made up of each of the digits 0 to 9 in some order, but it also has a rather interesting sub-string divisibility property.



Let d1 be the 1st digit, d2 be the 2nd digit, and so on. In this way, we note the following:




  • d2d3d4=406 is divisible by 2


  • d3d4d5=063 is divisible by 3


  • d4d5d6=635 is divisible by 5


  • d5d6d7=357 is divisible by 7


  • d6d7d8=572 is divisible by 11


  • d7d8d9=728 is divisible by 13


  • d8d9d10=289 is divisible by 17



Find the sum of all 0 to 9 pandigital numbers with this property.








My Solution Using Mathematica



For[i = 362880, i < 3628801, i++, TempList = NthPermutation[i, MyList];



 For[j = 2, j < 9, j++, 


  If[! Divisible[FromDigits[TempList[[j ;; (j + 2)]]], 


     DivisorList[[j - 1]]], Flag = False; Break[]]];If[Flag, TotalSum = TotalSum + FromDigits[TempList]; Flag = True;]


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