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We ought never to allow ourselves to be persuaded of the truth of anything unless on the evidence of our own reason
– René Descartes
Number Theory

A Rational Number With a Finite Number of Digits

Proof: The sum of any three singledigit numbers is at most two digits long

Proof: a natural number n is a prime if b^(n−1) = 1 (mod n) for every integer b between 1 and n1

A number is divisible by 3 iff sum of its digits are divisible by 3

Prove that b  a iff every multiple of a is multiple of b

Prove or disprove if a+b=2 then b+z=3 for some z
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