Problem 54680. Determine whether a number is practical

A number n is practical if all smaller numbers can be written as a sum of the proper divisors of n. The number 24 is practical because its proper divisors are 1, 2, 3, 4, 6, 8, and 12 and for example
5 = 4+1, 7 = 4+3, 9 = 6+3, 10 = 8+2, 11 = 8+3, 13 = 12+1, 14 = 12+2, 15 = 12+3, 16 = 12+4,
17 = 12+4+1, 18 = 12+6, 19 = 12+3+4, 20 = 12+8, 21 = 12+8+1, 22 = 12+8+2, 23 = 12+8+3
However, 23 is not practical because its only proper divisor, 1, cannot be repeated in the sum.
Write a function to determine whether a number is practical.
Solve

Solution Stats

30.0% Correct | 70.0% Incorrect
Last Solution submitted on Apr 08, 2023

Problem Comments

Solution Comments

Show comments

Problem Recent Solvers6

Suggested Problems

More from this Author312

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!