Conditions of Digit in The Places of Positive Integers Divisible by 7

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Thanatyod Jampawai


We study conditions of digit in the places of positive integers divisible by gif.latex?7 . We found that the sum of products of digit in the ones place, tens place, hundreds place, thousands place, ten thousands place, hundred thousands place, millions place, ten millions place, hundred millions place, billions place, ten billions place, hundred billions place, gif.latex?\ldots  and gif.latex?1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,\ldots,  respectively, is divisible by gif.latex?7. In addition, we study conditions of positive integers with same digits which are divisible by gif.latex?7.


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Jampawai, T. (2021). Conditions of Digit in The Places of Positive Integers Divisible by 7. Mathematical Journal by The Mathematical Association of Thailand Under The Patronage of His Majesty The King, 66(705), 52–64. Retrieved from
Research Article


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