Re:On Primes and Pluto
by thaumasiotes on Friday March 07, 2014 @06:02AM
(#7359572)
This has been covered by anaphor, but to respond to the question directly:
No, a prime number, for example 5, is not the product of 1 and itself (at least, no more than it's the product of 1/3 and 15). It is the product of itself only, so it can be represented as a set of factors like {5}. 1 is the product of nothing, and would be represented as the set of factors {}.
Multiplication, obviously, just combines the factors of the multiplicands. 6 (= {2,3}) times 2 (= {2}) equals {2,2,3}, 12. Hopefully that makes it clear why 1 should be {}.
No, a prime number, for example 5, is not the product of 1 and itself (at least, no more than it's the product of 1/3 and 15). It is the product of itself only, so it can be represented as a set of factors like {5}. 1 is the product of nothing, and would be represented as the set of factors {}.
Multiplication, obviously, just combines the factors of the multiplicands. 6 (= {2,3}) times 2 (= {2}) equals {2,2,3}, 12. Hopefully that makes it clear why 1 should be {}.