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id	title	challengeType	forumTopicId	dashedName
5900f3ef1000cf542c50ff01	Problem 129: Repunit divisibility	5	301756	problem-129-repunit-divisibility

--description--

A number consisting entirely of ones is called a repunit. We shall define R(k) to be a repunit of length k; for example, R(6) = 111111.

Given that n is a positive integer and GCD(n, 10) = 1, it can be shown that there always exists a value, k, for which R(k) is divisible by n, and let A(n) be the least such value of k; for example, A(7) = 6 and A(41) = 5.

The least value of n for which A(n) first exceeds ten is 17.

Find the least value of n for which A(n) first exceeds one-million.

--hints--

euler129() should return 1000023.

assert.strictEqual(euler129(), 1000023);

--seed--

--seed-contents--

function euler129() {

  return true;
}

euler129();

--solutions--

// solution required

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