freeCodeCamp/curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-37-truncatable-primes.english.md

id, challengeType, title, forumTopicId

id	challengeType	title	forumTopicId
5900f3911000cf542c50fea4	5	Problem 37: Truncatable primes	302031

Description

The number 3797 has an interesting property. Being prime itself, it is possible to continuously remove digits from left to right, and remain prime at each stage: 3797, 797, 97, and 7. Similarly we can work from right to left: 3797, 379, 37, and 3.

Find the sum of the only n (8 ≤ n ≤ 11) primes that are both truncatable from left to right and right to left.

NOTE: 2, 3, 5, and 7 are not considered to be truncatable primes.

Instructions

Tests

tests:
  - text: <code>truncatablePrimes(8)</code> should return a number.
    testString: assert(typeof truncatablePrimes(8) === 'number');
  - text: <code>truncatablePrimes(8)</code> should return 1986.
    testString: assert(truncatablePrimes(8) == 1986);
  - text: <code>truncatablePrimes(9)</code> should return 5123.
    testString: assert(truncatablePrimes(9) == 5123);
  - text: <code>truncatablePrimes(10)</code> should return 8920.
    testString: assert(truncatablePrimes(10) == 8920);
  - text: <code>truncatablePrimes(11)</code> should return 748317.
    testString: assert(truncatablePrimes(11) == 748317);

Challenge Seed

function truncatablePrimes(n) {

  return n;
}

truncatablePrimes(11);

Solution

// solution required