https://en.wikipedia.org/wiki/Divisibilityarrow-up-right
Divisibility := If a and b are ints, then a divides b if b = a*n for some int n. a is called a factor or divisor of b. b is called a multiple of a.
a
b
b = a*n
n
shorthand a divides b is a | b i.e. divisor | multiple
a divides b
a | b
divisor | multiple
(ab e Z AND b=a*n) . a | b
int p is even exactly when 2 | p
p
2 | p
zero being even is a special case cuz zero is divisible by any int
Last updated 4 years ago