Problem 52664. List the Moran numbers

Created by ChrisR
Appears in Prime Numbers III

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The quotient of a Moran number and its digit sum is prime. For example, 117 and 481 are Moran numbers because 117/(1+1+7) is 13 and 481/(4+8+1) = 37, and both 13 and 37 are prime. 
Write a function to list the Moran numbers less than or equal to the input number. 

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Last Solution submitted on Jun 04, 2025

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GeeTwo on 1 Dec 2024

@Tim, thanks for the idea of using ismember(). It greatly simplified my already simplest solution to date. All I did before was squeeze a literal implementation and make it work just fast enough to fit the one-minute filter..Your inspiration took me from four statements to two.

ty on 3 Jun 2025 at 7:04

I believe I have the right solution but it is not fast enough, can anyone advise me on how to get the digit sum without using a for loop?

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Problem 52664. List the Moran numbers

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Last 200 Solutions

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Problem 52664. List the Moran numbers

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers15

Suggested Problems

More from this Author301

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Community Treasure Hunt

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