3 is the second prime number, and the second single digit prime number. 3's prime factors are 1 and 3. It is said to be the first odd prime, because the previous prime number is [[2]], which is even.

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3 is the second prime number, and the second single digit prime number. 3's prime factors are 1 and 3. It is said to be the first odd prime, because the previous prime number is [[2]], which is even.

==Proofs==

==Proofs==

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**3 and 7 are four numbers apart, therefore, they are cousin primes.

**3 and 7 are four numbers apart, therefore, they are cousin primes.

*9, the odd number following 7, is not a prime number. It is a square number, and the first odd composite number.

*9, the odd number following 7, is not a prime number. It is a square number, and the first odd composite number.

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==Usage==

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===Science===

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*Lithium's atomic number and number of electrons are 3.

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*Group three elements also have the valence of +3. Similarly, group five elements have the valence of -3.

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*Tritium / hydrogen-3, has a nucleon number of 3.

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===Sports===

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*In basketball, a shot behind the three-point arc is worth three points, unless in the 3x3 variant.

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===Video Games===

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*In The Legend of Zelda series, there is a sacred relic called Triforce, which consists of three separate golden triangles.

Revision as of 07:50, December 15, 2013

3 is the second prime number, and the second single digit prime number. 3's prime factors are 1 and 3. It is said to be the first odd prime, because the previous prime number is 2, which is even.

Proofs

It is divisible by 1: 3/1=3

It is not divisible by 2: 3/2=1.5

It is divisible by 3: 3/3=1

Therefore it has 2 factors, not 3, because 3 divided by 2 does not result in an integer value.

Relationship with other odd numbers

The numbers before

2 is the first prime number. It is the only even prime number.