6 ms·
That's not true for x=2 : 2^4 = 6 mod 10 Also, 4 does not divide the order of the multiplicative group of Z/2Z. i.e. 4 does not divide 1. (Also, the claim was t
by knappa 9y ago
That's not true for x=2 : 2^4 = 6 mod 10
Also, 4 does not divide the order of the multiplicative group of Z/2Z. i.e. 4 does not divide 1.
(Also, the claim was that x^5 = x mod 10 not x^5=1, but I assume that's a typo.)
- contravariant 9y agoHmm yes I suppose I was a bit sloppy, although I got the gist of it right somehow. I guess the problem here is that x^4 = 1 mod 2 is false if x = 0 mod 2, but x^5 = x mod 2 does hold for all numbers. I've fixed the problems you mentioned, thanks.