freeCodeCamp/curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-155-counting-capacitor-circuits.md

id, title, challengeType, forumTopicId, dashedName

id	title	challengeType	forumTopicId	dashedName
5900f4081000cf542c50ff1a	Problem 155: Counting Capacitor Circuits	5	301786	problem-155-counting-capacitor-circuits

--description--

An electric circuit uses exclusively identical capacitors of the same value C.

The capacitors can be connected in series or in parallel to form sub-units, which can then be connected in series or in parallel with other capacitors or other sub-units to form larger sub-units, and so on up to a final circuit. Using this simple procedure and up to n identical capacitors, we can make circuits having a range of different total capacitances. For example, using up to n=3 capacitors of 60 F each, we can obtain the following 7 distinct total capacitance values:

If we denote by D(n) the number of distinct total capacitance values we can obtain when using up to n equal-valued capacitors and the simple procedure described above, we have: D(1)=1, D(2)=3, D(3)=7 ... Find D(18). Reminder : When connecting capacitors C1, C2 etc in parallel, the total capacitance is CT = C1 + C2 +...,

whereas when connecting them in series, the overall capacitance is given by:

--hints--

euler155() should return 3857447.

assert.strictEqual(euler155(), 3857447);

--seed--

--seed-contents--

function euler155() {

  return true;
}

euler155();

--solutions--

// solution required