1 and Prime Numbers - Numberphile

Is 1 a prime number? Apparently not. Dr James Grime explains.

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James Grime's website is: http://singingbanana.com/

Category:

Science & Technology

Tags:

• number phile
• number
• numbers
• maths
• mathematics
• mathematical
• numerals
• count
• counting
• arithmetic

[MippieMan]

love the enthusiasm of that guy xD. I didn't find the very last explanation very satisfying though..

[SomeoneCommenting]

@spairpartsdealer That's from Three Dog Night, not the Beatles.

[TeamAvatar2000]

i like this guy

[yonoid818]

@slasherrs9 Isn't that begging the question? He was using that to explain why 1 is not a prime. You can't assume that 1 is not a prime and then use it in the "proof" that 1 is not a prime.

[slasherrs9]

@yonoid818 it's being argued that 1 is not prime, so it can't be included as a "unique product of primes" for any number, including itself. on the other hand, 2 is prime and it is represented as a product of just one number- 2

[xXgAvInArNoLdXx]

@A4N3O2N1 Whatr I'm saying is a half x 2 or 1/2x2 (cant type fractions)

[DKarlHungus]

@MippieMan The last explanation could be looked at as 16=2^4

8=2^3  4=2^2 2=2^1 and finally 1=2^0. As you can see they call it an empty prime because any number (therefore primes) to the power of 0 will equal 1. Hence any prime to the 0 power is considered an empty prime I believe.

[yonoid818]

How can 2 be a product of 2? Couldn't 1 then simply be a product of 1, and not zero primes?

[TheMrwtfwasthat]

1 = 0000 0001

[ZiqqiPH]

*forever alone*