Anagramic squaresBy replacing each of the letters in the word CARE with 1, 2, 9, and 6 respectively, we form a square number: 1296 = 362. What is rema...
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其他好文 时间：
2015-12-07 22:42:29
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343
Amicable chainsThe proper divisors of a number are all the divisors excluding the number itself. For example, the proper divisors of 28 are 1, 2, 4, 7...
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2015-12-05 20:52:12
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166
Amicable chainsThe proper divisors of a number are all the divisors excluding the number itself. For example, the proper divisors of 28 are 1, 2, 4, 7...
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其他好文 时间：
2015-12-05 00:25:25
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327
最大流求混合图是否存在欧拉回路。以下内容摘自http://www.cnblogs.com/Missa/archive/2012/12/05/2803107.html 讲的很清楚。混合图的欧拉回路问题 欧拉回路问题。 1 定义 欧拉通路 (Euler tour)——通过图中每条边一次且仅一次，并且过每...
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其他好文 时间：
2015-12-02 22:09:53
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142
Right triangles with integer coordinatesThe points P (x1, y1) and Q (x2, y2) are plotted at integer co-ordinates and are joined to the origin, O(0,0),...
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其他好文 时间：
2015-11-30 22:20:59
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239
Product-sum numbersA natural number, N, that can be written as the sum and product of a given set of at least two natural numbers, {a1, a2, … , ak} is...
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其他好文 时间：
2015-11-29 17:51:10
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263
Prime power triplesThe smallest number expressible as the sum of a prime square, prime cube, and prime fourth power is 28. In fact, there are exactly ...
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其他好文 时间：
2015-11-27 21:37:09
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201
Cuboid routeA spider, S, sits in one corner of a cuboid room, measuring 6 by 5 by 3, and a fly, F, sits in the opposite corner. By travelling on the s...
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其他好文 时间：
2015-11-27 20:01:21
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231
题目要求是：If 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...
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其他好文 时间：
2015-11-27 19:30:21
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136
Counting rectanglesBy counting carefully it can be seen that a rectangular grid measuring 3 by 2 contains eighteen rectangles:Although there exists no...
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其他好文 时间：
2015-11-26 23:03:54
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205
