Euler's Totient function, φ(n) [sometimes called the phi function], is used to determine the number of numbers less than n which are relatively prime to n.
For example, as 1, 2, 4, 5, 7, and 8, are ...
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其他好文 时间：
2015-07-17 10:05:11
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174
By starting at the top of the triangle below and moving to adjacent numbers on the row below, the maximum total from top to bottom is 23.
3
7 4
2 4 6
8 5 9 3
That is, 3 + 7 + 4 + 9 = 23.
Find th...
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其他好文 时间：
2015-07-16 09:52:17
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155
Triangle, square, pentagonal, hexagonal, heptagonal, and octagonal numbers are all figurate (polygonal) numbers and are generated by the following formulae:
Triangle
P3,n=n(n+1)/2
1, 3,...
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其他好文 时间：
2015-07-14 18:23:07
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83
The cube, 41063625 (3453), can be permuted to produce two other cubes: 56623104 (3843) and 66430125 (4053). In fact, 41063625 is the smallest cube
which has exactly three permutations of its digits ...
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其他好文 时间：
2015-07-14 18:21:53
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113
The 5-digit number, 16807=75, is also a fifth power. Similarly, the 9-digit number, 134217728=89, is a ninth power.
How many n-digit positive integers exist which are also an nth power?
这样的数字满...
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其他好文 时间：
2015-07-14 17:58:13
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195
除1,1其他外国x,y不等于为 x#include #include #include using namespace std;const int maxn=55000;long long int phi[maxn];void phi_table(){ phi[1]=1LL; for(i...
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其他好文 时间：
2015-07-13 18:06:44
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99
Starting with 1 and spiralling anticlockwise in the following way, a square spiral with side length 7 is formed.
37 36 35 34 33 32 31
38 17 16 15 14 13 30
39 18 5 4 3 12 29
40 19 6 1 2 11 ...
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其他好文 时间：
2015-07-08 22:37:59
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218
1.增加虚拟网络命名空间ip netns add net02.显示所有的虚拟网络命名空间EULER:~ #ip netns listnet0也可通过查看/var/run/netns目录下的文件来listEULER:~ #ls /var/run/netns/net03.进入虚拟机网络环境ip netn...
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Web程序 时间：
2015-07-08 20:38:28
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178
A googol (10100) is a massive number: one followed by one-hundred zeros; 100100 is almost unimaginably large: one followed by two-hundred zeros. Despite their
size, the sum of the digits in each num...
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其他好文 时间：
2015-07-08 09:39:56
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101
In the card game poker, a hand consists of five cards and are ranked, from lowest to highest, in the following way:
High Card: Highest value card.One Pair: Two cards of the same value.Two Pairs: Tw...
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其他好文 时间：
2015-07-07 17:09:16
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131
