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Arithmetic Course/Types of Number/Natural Number
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Natural Number
Natural Number is a set of all digits from 0 to 9
N = {1,2,3,4,5,6,7,8,9}
Even Number
Natural Number divisible by two is called Even Number
2N = {2,4,6,8}
Odd Number
Natural Number not divisible by two is called Odd Number
2N + 1 = {1,3,5,7,9}
Prime Number
prime number"p"" is the number that have 4 divisors [p,-p,1,-1]
p=[2,3,5,7,9,11,.................]