Put m=1
2^4=16
16-1=15
15 is divisible on 15...
Answer is yes......(2^4m)-1 is divisible on 15.....
–
Shahzad Saleem
·
1 year, 8 months ago

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@Shahzad Saleem
–
You did not prove it, you just checked a case. Checking a case that does not represent all other cases is not a proof.
–
Anupam Nayak
·
1 year, 7 months ago

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TopNewest2^4 = 1 (mod 15) or, 2^4m = 1 (mod 15) or, 2^4m -1 = 0 (mod 15)

And it's proved. – Mahadi Hasan · 1 year, 7 months ago

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Put m=1 2^4=16 16-1=15 15 is divisible on 15... Answer is yes......(2^4m)-1 is divisible on 15..... – Shahzad Saleem · 1 year, 8 months ago

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– Anupam Nayak · 1 year, 7 months ago

You did not prove it, you just checked a case. Checking a case that does not represent all other cases is not a proof.Log in to reply