f(n) is the number of intergers smaller than n and with no

Question

f(n) is the number of intergers smaller than n and with no common factor with n other than 1. 

When p is prime, what is f(p) in terms of p?

allabout · Answer

Don't know if I've understand this question correctly, but if p is prime then
 
0<each number<p, thus

f(p)= p-1... with p>1





Is 0 a factor of 3?

duttsit · Answer

Agree. the same should work for p = 1 as well IMO. if p = 1 f(p) = 0

the question, i guess, should say "the number of non-negative integers" to be more clear.

lhotseface · Answer

I get f(p) = p -2, please evaluate...

Since p is prime, the first possible value is 2.

f(2) = 0 .
f(3) = 1. ( only 2 is the possible number ).
f(5) = 3 ( only 2,3,4)
f(7) = 5 ( only 2,3,4,5,6)
...
f(p) = p-2.

believe2 · Answer

..but you have to include 1. 
the Q is "f(n) is the  number of intergers smaller than n  and with no common factor with n other than 1. "

lhotseface · Answer

Thanks a ton...I tend to read too much in to problems.

andy_gr8 · Answer

p-1 for me too
f(2)=1
f(3)= 2 (2,1)
f(5)= 4 (4,3,2,1)

f(n) is the number of intergers smaller than n and with no

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