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gikf c18554dd44 fix(curriculum): clean-up Project Euler 341-360 (#42998)
* fix: clean-up Project Euler 341-360

* fix: improve wording

Co-authored-by: Sem Bauke <46919888+Sembauke@users.noreply.github.com>

* fix: corrections from review

Co-authored-by: Tom <20648924+moT01@users.noreply.github.com>

Co-authored-by: Sem Bauke <46919888+Sembauke@users.noreply.github.com>
Co-authored-by: Tom <20648924+moT01@users.noreply.github.com>
2021-07-29 19:14:22 +02:00

944 B

id, title, challengeType, forumTopicId, dashedName
id title challengeType forumTopicId dashedName
5900f4c71000cf542c50ffd8 Problem 346: Strong Repunits 5 302005 problem-346-strong-repunits

--description--

The number 7 is special, because 7 is 111 written in base 2, and 11 written in base 6 (i.e. 7_{10} = {11}_6 = {111}_2). In other words, 7 is a repunit in at least two bases b > 1.

We shall call a positive integer with this property a strong repunit. It can be verified that there are 8 strong repunits below 50: {1, 7, 13, 15, 21, 31, 40, 43}. Furthermore, the sum of all strong repunits below 1000 equals 15864.

Find the sum of all strong repunits below {10}^{12}.

--hints--

strongRepunits() should return 336108797689259260.

assert.strictEqual(strongRepunits(), 336108797689259260);

--seed--

--seed-contents--

function strongRepunits() {

  return true;
}

strongRepunits();

--solutions--

// solution required