curriculum/challenges/english/blocks/project-euler-problems-1-to-100/5900f3ce1000cf542c50fee0.md
The first known prime found to exceed one million digits was discovered in 1999, and is a Mersenne prime of the form $2^{6972593} − 1$; it contains exactly 2,098,960 digits. Subsequently other Mersenne primes, of the form $2^p − 1$, have been found which contain more digits.
However, in 2004 there was found a massive non-Mersenne prime which contains 2,357,207 digits: $28433 × 2^{7830457} + 1$.
Find the last ten digits of that non-Mersenne prime in the form $multiplier × 2^{power} + 1$.
largeNonMersennePrime(19, 6833086) should return a string.
assert(typeof largeNonMersennePrime(19, 6833086) === 'string');
largeNonMersennePrime(19, 6833086) should return the string 3637590017.
assert.strictEqual(largeNonMersennePrime(19, 6833086), '3637590017');
largeNonMersennePrime(27, 7046834) should return the string 0130771969.
assert.strictEqual(largeNonMersennePrime(27, 7046834), '0130771969');
largeNonMersennePrime(6679881, 6679881) should return the string 4455386113.
assert.strictEqual(largeNonMersennePrime(6679881, 6679881), '4455386113');
largeNonMersennePrime(28433, 7830457) should return the string 8739992577.
assert.strictEqual(largeNonMersennePrime(28433, 7830457), '8739992577');
function largeNonMersennePrime(multiplier, power) {
return true;
}
largeNonMersennePrime(19, 6833086);
function largeNonMersennePrime(multiplier, power) {
function modStepsResults(number, other, mod, startValue, step) {
let result = startValue;
for (let i = 0; i < other; i++) {
result = step(number, result) % mod;
}
return result;
}
const numOfDigits = 10;
const mod = 10 ** numOfDigits;
const digitsAfterPower = modStepsResults(2, power, mod, 1, (a, b) => a * b);
const digitsAfterMultiply = modStepsResults(
digitsAfterPower,
multiplier,
mod,
0,
(a, b) => a + b
);
const lastDigits = (digitsAfterMultiply + 1) % mod;
return lastDigits.toString().padStart(10, '0');
}