Every Digits in Number of a Range Should Be Is Divisible by N

A given number from 2 to N should have each number divisible outputted as [(2,4), (2,6),( 2,8),( 3,9),( 3,12), (3,15) .....] in Python 2/3

NOTE: Any number divisible by n (where n is a whole number - 1, 2, 3, 4 ...) is a multiple of n.

You can try:

n = int(input("Enter a number: "))

multiples = [(a, b) for a in range(2, n + 1) for b in range(2, n + 1) if b%a == 0 and a != b]

print (multiples)

where n is the number "below" which the number of multiples is printed for a specific number, but using n + 1 prints the number of multiples "up to" n (only if it is possible).

For example, when n = 10, it will give this output, [(2, 4), (2, 6), (2, 8), (2, 10), (3, 6), (3, 9), (4, 8), (5, 10)].

This has two conditions: b%a == 0, which makes sure that a is not zero, as b / 0 == math error and b%a checks whether the second number is a factor of the first number, or not.

Without b%a == 0, you would have:

[(2, 3), (2, 4), (2, 5), (2, 6), (2, 7), (2, 8), (2, 9), (3, 2), (3, 4), (3, 5), (3, 6), (3, 7), (3, 8), (3, 9), (4, 2), (4, 3), (4, 5), (4, 6), (4, 7), (4, 8), (4, 9), (5, 2), (5, 3), (5, 4), (5, 6), (5, 7), (5, 8), (5, 9), (6, 2), (6, 3), (6, 4), (6, 5), (6, 7), (6, 8), (6, 9), (7, 2), (7, 3), (7, 4), (7, 5), (7, 6), (7, 8), (7, 9), (8, 2), (8, 3), (8, 4), (8, 5), (8, 6), (8, 7), (8, 9), (9, 2), (9, 3), (9, 4), (9, 5), (9, 6), (9, 7), (9, 8)]

Since you do not want a equal to b (3 == 3), you can use a != b, so don't have to worry about getting (3, 3) or (4, 4) etc.

To get the maximum number of multiples for a good range of numbers ( 2 to n) , I would use a larger sample such as n = 50, which will give this output:

[(2, 4), (2, 6), (2, 8), (2, 10), (2, 12), (2, 14), (2, 16), (2, 18), (2, 20), (2, 22), (2, 24), (2, 26), (2, 28), (2, 30), (2, 32), (2, 34), (2, 36), (2, 38), (2, 40), (2, 42), (2, 44), (2, 46), (2, 48), (2, 50), (3, 6), (3, 9), (3, 12), (3, 15), (3, 18), (3, 21), (3, 24), (3, 27), (3, 30), (3, 33), (3, 36), (3, 39), (3, 42), (3, 45), (3, 48), (4, 8), (4, 12), (4, 16), (4, 20), (4, 24), (4, 28), (4, 32), (4, 36), (4, 40), (4, 44), (4, 48), (5, 10), (5, 15), (5, 20), (5, 25), (5, 30), (5, 35), (5, 40), (5, 45), (5, 50), (6, 12), (6, 18), (6, 24), (6, 30), (6, 36), (6, 42), (6, 48), (7, 14), (7, 21), (7, 28), (7, 35), (7, 42), (7, 49), (8, 16), (8, 24), (8, 32), (8, 40), (8, 48), (9, 18), (9, 27), (9, 36), (9, 45), (10, 20), (10, 30), (10, 40), (10, 50), (11, 22), (11, 33), (11, 44), (12, 24), (12, 36), (12, 48), (13, 26), (13, 39), (14, 28), (14, 42), (15, 30), (15, 45), (16, 32), (16, 48), (17, 34), (18, 36), (19, 38), (20, 40), (21, 42), (22, 44), (23, 46), (24, 48), (25, 50)]

Hope this helps!

Python prime numbers for noobies

We know a number will be a prime number if and only if it is divisible by 1 and the number itself. If it is divisible by any number within the range from 2 to (number - 1) then it will not be a prime number.

So in the second loop of the given code we are checking whether the number is divisible by any number within the range 2 to (number - 1) or not.

Example 1:
number = 5
i values = 2, 3, 4
So here none of the i values divides 5. So, 5 is a prime number.

Example 2:
number = 6
i values = 2, 3, 4, 5
here 2 divides 6 so 6 is not a prime number.

Thank you.

Related Topics