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You are not logged in. #1 20060203 12:55:44
2520 A wonderfull little number2520 is my favorite number. I found her one day when I decided to find the least common multiple of the numbers 1 through 10 and we've been friends ever since! Last edited by mikau (20060203 12:56:13) A logarithm is just a misspelled algorithm. #2 20060203 13:10:12
Re: 2520 A wonderfull little numberTo quickly find all the numbers 2520 can be evenly divided by, I wrote a simple program to check divisibilty for me. Its simple but pretty cool. Code:#include <iostream> int main() { long int counter = 0; float F; long int I; long int N = 2520; for (float i = 1; i <= N; i++) { F = N/i; I = F; if (I == F) { std::cout << " " << i << ","; counter++;} } std::cout << "\n\n " << counter << " found\n"; return 0; } } It simply checks the divisibility of N by dividing by every integer from 1 to N. Each time the quotient is assigned to a float variable "F" which strores a decimal number. Then an integer variable I is assigned the value of F. In C++, if a decimal number is assigned to an integer, the value will be truncated (basicly anything behind the decimal point is "chopped off"). The program then checks to see if I and F are equal. If they are, that means the integer was not truncated, which only happens if the float value was an integer. Which would only happen if N was divided by a divisble number. So if F and I are equal, the number checked is printed. :) A logarithm is just a misspelled algorithm. #3 20060203 13:22:31
Re: 2520 A wonderfull little number2*2*2*2*3*3*5*7*11*13 = 720,720 (Least common multiple of 1 throuh 16.) divisible by: Last edited by mikau (20060203 13:25:42) A logarithm is just a misspelled algorithm. #4 20060204 10:01:12
Re: 2520 A wonderfull little numberFascinating stuff! "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #5 20060204 12:15:11
Re: 2520 A wonderfull little numberYeah 2520 is the LCM of the numbers 1 through 10. For 1 through 11 we need an addition factor of 11 which brings it up to 27,720. This is also the lcm of 1 to 12 since we already have the factors of 12 present. For 1 to 13 we need an additional factor of 13 which brings it up to 360,360. The factors of 14 and 15 are already present so this is also the lcm of 1 to 15. For a factor of 16 we need an additional factor of 2, (we only have three) that brings it up to 720,720. A logarithm is just a misspelled algorithm. #6 20060206 13:34:13
Re: 2520 A wonderfull little number100110100000 in binary, 9D8 in hex, 10230 in 7..... that's all I care about #7 20060301 06:04:28
Re: 2520 A wonderfull little numberWell I've addapted 720,720 as my new favorite number. Originally I didn't investigate any further then 4 digits as it became hard to remember, but 720,720 is easy to remember! A logarithm is just a misspelled algorithm. #8 20060301 06:11:16
Re: 2520 A wonderfull little numberYou can compute the number IPBLE: Increasing Performance By Lowering Expectations. #9 20060301 06:18:50
Re: 2520 A wonderfull little numberThe number 30030 is divisible to all the numbers less than 17 and it's easy to remember. IPBLE: Increasing Performance By Lowering Expectations. #10 20060301 06:24:08
Re: 2520 A wonderfull little numberOthen easytoremember numbers are: IPBLE: Increasing Performance By Lowering Expectations. #11 20060302 08:46:29
Re: 2520 A wonderfull little numbersweet stuff! A logarithm is just a misspelled algorithm. #12 20060304 08:52:00
Re: 2520 A wonderfull little numberya, swweett IPBLE: Increasing Performance By Lowering Expectations. 