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Quick Divisiblity Proof (Posted on 2019-02-14)

Prove that all numbers of the form 12008, 120308, 1203308, ... are divisible by 19.

No Solution Yet Submitted by Danish Ahmed Khan

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a simple proof

| Comment 1 of 3

Since

a(1) is divisible by 19

and

a(n+1) =10*a(n+1) +228

and

228 is divisible by 19

the proof "by induction"is completed (true for n=> true for n+1)

Edited on February 14, 2019, 8:20 am

Posted by Ady TZIDON on 2019-02-14 08:16:19

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