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package xxx.xxx.xxx;import java.util.ArrayList;import java.util.Arrays;/* * Euler discovered the remarkable quadratic formula:n² + n + 41 * It turns out that the formula will produce

package xxx.xxx.xxx;/* * The sequence of triangle numbers is generated by adding the natural numbers. So the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. * The first ten term

package xxx.xxx.xxx;import java.io.BufferedReader;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStreamReader;import java.math.BigInt

package xxx.xxx.xxx;import java.math.BigInteger;import java.util.ArrayList;import java.util.Arrays;import java.util.List;/* * The following iterative sequence is defined for the se

package xxx.xxx.xxx;import java.math.BigInteger;/* * 2^15 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26. * What is the sum of the digits of the number 21000? */public

package xxx.xxx.xxx;import java.math.BigInteger;/* * n! means n × (n − 1) × ... × 3 × 2 × 1 * For example, 10! = 10 × 9 × ... × 3 × 2 × 1 = 3628800, * and the sum of the digits in th

package xxx.xxx.xxx;import java.util.ArrayList;/* * You are given the following information, but you may prefer to do some research for yourself. * 1 Jan 1900 was a Monday. * Thirty

package xxx.xxx.xxx;/* * Let d(n) be defined as the sum of proper divisors of n (numbers less than n which divide evenly into n). * If d(a) = b and d(b) = a, where a ≠ b, then a and b are an ami

package xxx.xxx.xxx;import java.util.HashSet;/* * A perfect number is a number for which the sum of its proper divisors is exactly equal to the number. * For example, the sum of the pr

package xxx.xxx.xxx;import java.util.ArrayList;import java.util.HashSet;/* * We shall say that an n-digit number is pandigital if it makes use of all the digits 1 to n exactly once; fo

package xxx.xxx.xxx;import java.math.BigInteger;/* * The Fibonacci sequence is defined by the recurrence relation: * Fn = Fn−1 + Fn−2, where F1 = 1 and F2 = 1. * Hence the first 12 t

package xxx.xxx.xxx;/* * A permutation is an ordered arrangement of objects. For example, 3124 is one possible permutation of the digits 1, 2, 3 and 4. * If all of the permutations are listed nu

package xxx.xxx.xxx;/* * A Pythagorean triplet is a set of three natural numbers, a  * For example, 3^2 + 4^2 = 9 + 16 = 25 = 5^2. * There exists exactly one Pythagorean triplet for which

package xxx.xxx.xxx;/* * Using names.txt (right click and 'Save Link/Target As...'), a 46K text file containing over five-thousand first names, begin by sorting it into alphabetical order. *

package xxx.xxx.xxx;import java.math.BigInteger;/* * The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. * Find the sum of all the primes below two million. */public class Su

package xxx.xxx.xxx;/* * Starting with the number 1 and moving to the right in a clockwise direction a 5 by 5 spiral is formed as follows:21 22 23 24 2520  7  8  9 1019  6  1  2 1118  

Multiples of 3 and 5Problem 1If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.Find the sum of all the multiple

package zml.algorithm.test;// Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be: 1, 2, 3, 5, 8, 13, 21,

Largest prime factorThe prime factors of 13195 are 5, 7, 13 and 29.What is the largest prime factor of the number 600851475143 ?package zml.algorithm.test;import java.math.BigInteger

Largest palindrome productA palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 × 99.Find the largest palindrome made fr

package xxx.xxx.xxx;import java.util.ArrayList;/* * 2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder. * What is the smallest po

package xxx.xxx.xxx;/* * The sum of the squares of the first ten natural numbers is,1^2 + 2^2 + ... + 10^2 = 385 * The square of the sum of the first ten natural numbers is,(1 + 2 + ... + 10)^2

package xxx.xxx.xxx;public class NthtPrime {private void compute(int Nth) {int count = 2;int num = 3;label:while (true) {System.out.println(count);boolean isPrime = true;for

结论不正确，不知道为什么。package xxx.xxx.xxx;import java.util.ArrayList;/* * The four adjacent digits in the 1000-digit number that have the greatest product are 9 × 9 × 8 × 9 = 5832. * 7316

package xxx.xxx.xxx;/* * A unit fraction contains 1 in the numerator. * The decimal representation of the unit fractions with denominators 2 to 10 are given: 1/2 = 0.5 1/3 = 0.(3) 1/4 = 0.