RunKit + npm: d3-array

var results = []; for (var i = -20; i < 0; ++i) { [1, 2, 5, 10].forEach(k => { results.push([ (1 / (k * Math.pow(10, i))).toExponential(), (Math.pow(10, -i) / k).toExponential() ]); }); } results.join("\n");