Published
Edited
Dec 11, 2020
collapz(5)
collapz(7)
collapz(11)
collapz(27)
collapz(53)
collapzStepTally = (number) => {
const steps = {tripled: 0, halved: 0}
let updated = number;
while (updated !== 1) {
if (updated % 2 === 0) {
updated /= 2
steps.halved += 1
} else {
updated = 3 * updated + 1
steps.tripled += 1
}
}
return [steps.halved + steps.tripled, steps]
}
collapzWithBinaries = (number) => {
let steps = 0,
updated = number,
bins = [[number, number.toString(2)]],
longest = bins[0][1].length;
while (updated !== 1) {
updated = updated % 2 === 0 ? updated / 2 : 3 * updated + 1;
let bin = updated.toString(2);
longest = Math.max(longest, bin.length);
bins.push([updated, bin]);
steps++;
}
return [steps, bins.map(([num, bin]) => [num, bin.padStart(longest)])]
}
collapz27result = collapzWithBinaries(27)
collapzWithBinaries(53)
collapzWithBinaries(89)
function bigCollapz(bignumber){
let steps = 0;
let updated = BigInt(bignumber); // just in case a regular-sized int is provided
while (updated !== 1n) {
updated = (updated % 2n === 0n ? (updated / 2n) : (3n * updated + 1n));
steps++;
}
return steps
}
function bigBinCollapz(bignumber){
let steps = 0;
let updated = bignumber;
let bins = [bignumber.toString(2)];
let longest = bins[0].length;
while (updated !== 1n) {
updated = updated % 2n === 0n ? (updated / 2n) : (3n * updated + 1n);
let bin = updated.toString(2);
longest = Math.max(longest, bin.length);
bins.push(bin);
steps++;
}
// bins = bins.map(bin => bin.padStart(longest, " "))
return [steps, bins]
}
viewof numberOfNines = slider({min: 1, max: 7500, value: 2000, step: 1})
toTheNines = BigInt("9".repeat(numberOfNines))
bigBinCollapz(toTheNines)
import {slider} from "@jashkenas/inputs"
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
