It’s a lovely day. I took a walk around the campus after lunch. The scene was enjoyable in one deep autumn day. Before the afternoon work, I’d like to spend a few moments on the 24th Euler Problem. A permutation is an ordered arrangement of … Continue reading →

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Officially, it’s weekend. I’m solving this 23rd Euler problem just before my supper. 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 proper divisors … Continue reading →

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Just had my supper. Stomach is full of stewed beef and potato.  I’d like to solve the 22nd Euler problem before tonight work (right, I’ll work late in my office). Using names.txt (right click and ‘Save Link/Target As…’), a 46K text file containing over … Continue reading →

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It’s been over one month since my last post on Euler problem 20, when  I was planning to post at least one on either Euler project or visualization. So I am four posts behind; I’ll try to catch up. Tonight, I’ll solve the 21st Euler … Continue reading →

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It’s been quite a while since my last post on Euler problems. Today a visitor post his solution to the second problem nicely, which encouraged me to keep solving these problems. Just for fun! 10! = 10 * 9 * … * 3 * 2 * 1 … Continue reading →

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I’ve been working overtime last weekend. Although I suffered little from the Monday syndrome, I still need a break. So, I’m back to the Project Euler after days of Olympic data digging. Today, I’m gonna to solve the 19th problem. You are given the following … Continue reading →

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The 18th Euler problem is sorta a route finding problem. It has occupied my mind for two days. Finally I came up to a clever solution. Find the maximum total from top to bottom of the triangle below: 75 95 64 17 … Continue reading →

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It has been two weeks since my last post on the 16th Euler problem. Now, since I just need a break after supper, I’m coming the 17th problem. If the numbers 1 to 5 are written out in words: one, … Continue reading →

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The 16th problem is another big-number problem: 215 = 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? This … Continue reading →

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The 15th problem in Project Euler. Starting in the top left corner of a 22 grid, there are 6 routes (without backtracking) to the bottom right corner. How many routes are there through a 2020 grid? Mmm… walk in the … Continue reading →

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