Write a program that asks the user for a number `n`

and prints the sum of the numbers 1 to `n`

Write a program that asks the user for a number `n`

and gives him the possibility to choose between computing the sum and computing the product of 1,…,`n`

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Write a program that given a number n produces the times table for that number. Modify the previous program such that only multiples of three and five are considered in the sum, e.g. 3, 5, 9, 15 for `n`

=17

Write a program that prints all prime numbers.

Write a program that calculates the first 20 Triangle Numbers using Gauss’ Equation which says that to calculate the nth triangle number. Can you create a visually output? This could be either ASCII art or via a GUI.