Proof by Induction: Divisibility by 17

In summary, the conversation is discussing a proof by induction that a given expression is divisible by 17. The base case has been proven and the individual is currently stuck on the step case. They have tried manipulating the expression but are unable to continue. They conclude that the sum of two numbers divisible by 17 is also divisible by 17.
  • #1
guropalica
8
0
Proof by induction that 3 * 5^2n+1) + 2^3n+1 is divisible by 17!
Thanks in advance guys
 
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  • #2
In your expression, there is an ")" without an "(" --> 3 * 5^2n+1) + 2^3n+1

so it is not clear what do to!
 
  • #3
You also need to try yourself and let us know where you're stuck. Then we can help.
 
  • #4
I proved the base case n=1, and then I try doing the step case assuming that it satisfies for any k, then I try proving it by k+1.
I got sth like 24 * (3 * 5^(2k+1)) + 7 * 2^(3k +1) Now I'm stuck can't continue, I don't have any ideas :/
btw the initial equation is 3 * 5^(2n+1) + 2^(3n+1) !
 
  • #5
Got it now :) let's denote the initial statement as K + L, so we have sth like 24l + 7k = 7(k+l) + 17k, sum of two numbers divisible by 17 is divisible by 17, anyway thx
 

FAQ: Proof by Induction: Divisibility by 17

What is proof by induction?

Proof by induction is a mathematical technique used to prove that a statement is true for all natural numbers. It involves establishing a base case and then using a logical argument to show that if the statement is true for one natural number, it must also be true for the next natural number.

How does proof by induction apply to divisibility by 17?

Proof by induction can be used to prove that a certain formula or property involving divisibility by 17 is true for all natural numbers. This can be done by showing that the formula or property is true for the first few natural numbers and then using a logical argument to show that if it is true for one number, it must also be true for the next number.

What is the base case in a proof by induction for divisibility by 17?

The base case in a proof by induction for divisibility by 17 is typically showing that the statement is true for the first natural number, which is 1. This can be done by substituting 1 into the formula or property and showing that it is divisible by 17.

How does the inductive step work in a proof by induction for divisibility by 17?

The inductive step in a proof by induction for divisibility by 17 involves showing that if the statement is true for one natural number, it must also be true for the next natural number. This can be done by assuming the statement is true for a certain number and then using this assumption to show that it must also be true for the next number.

Are there any limitations to using proof by induction for divisibility by 17?

Yes, there are some limitations to using proof by induction for divisibility by 17. This technique can only be used to prove statements that involve natural numbers, and it may not be applicable for more complex formulas or properties. Additionally, it can be time-consuming to carry out the inductive step for larger numbers.

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