Programming
Coding in Python
Junior
For Loop Problems: Calculating Sums and Products

For Loop Problems: Calculating Sums and Products

Theory

Problems

Sum of Squares

Given a natural number n, calculate the sum:

1² + 2² + … + n²

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Full Problem

Factorial (for loop)

Compute N! (factorial of N) — the product of all natural numbers from 1 to N.

N! = 1 × 2 × 3 × … × N

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Full Problem

Power

Write a program that calculates 2^N.

The use of the exponentiation operator is forbidden.

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Full Problem

Binomial Coefficient

Given natural numbers n and k, compute the value of the binomial coefficient:

C(n, k) = n! / (k! × (n − k)!)

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Full Problem

Geometric Progression

Given a real number a and a natural number n, compute the sum:

1 + a + a² + … + aⁿ

You are not allowed to use the formula for the sum of a geometric progression or the exponentiation operator.

The program’s running time must be proportional to n.

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Full Problem

For Loop Sum – 1

Given a number n, compute the sum:

1 + 1/2² + 1/3² + … + 1/n²

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Full Problem

For Loop Sum – 2

Given a number n, compute the sum:

4 × (1 − 1/3 + 1/5 − 1/7 + … + (−1)ⁿ / (2n+1))

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Full Problem

Sum of Powers

Given a natural number N, compute the sum:

1 + 2 + 2² + 2³ + … + 2^N

The use of the exponentiation operator is forbidden.

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Full Problem
Intro to Python
Data Types
Type Conversion
Data Input: input() function
Data Output: print() function
Our First Program
Turtle: Pong Game
Arithmetic Operations
Conditional Statements in Python
Nested Conditions
Boolean in Python
Logical Operators
Cascading Conditional Statements in Python
For Loop Problems: Calculating Sums and Products

FAQ

Find quick answers to common questions about our lessons, pricing, scheduling, and how Exact Science can help your child excel.
Where do you hold your classes?
We hold our classes online or on-site on Saturdays at our branch in Pimlico Academy, London.
You can find our timetable here.
What do you need to start learning online?
For lessons you only need a computer or phone with a microphone, camera and Internet access. Wherever you are - in London, Nottingham, New York or Bali - online lessons will be at hand.
When can I take the trial lesson?
You can get acquainted with the school at any time convenient for you. To do this, just leave a request and sign up for a lesson.
What should I expect from the trial lesson?
The trial lesson is a 30-minute online session designed to get a sense of how your child approaches mathematical thinking and problem solving. (In practice, it often runs a bit longer if the student is engaged!)

We typically explore a range of fun and challenging problems drawn from competitions. We adapt the difficulty based on how the student responds, aiming to make it both accessible and stimulating.

After the session, we’ll have a quick conversation with the parent to share observations and suggest a personalised path forward.
I can't attend class, what should I do?
It is OK, it happens! Students have the opportunity to cancel a lesson up to 8 hours before the scheduled time without loss of payment. So you can reschedule it for a convenient time, and the teacher will have the opportunity to
I don't have much free time, will I have time to study?
Learning can take place at your own pace. We will select a convenient schedule and at any time we will help you change the schedule, take a break or adjust the program.
How long is one lesson?
All classes last 1 hour.

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Founder &
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