Code to generate hexadecimal values of all colors

Hi guys I need to generate a list of all possible 16 million colors in the 6 digit hexadecimal notation - how can that be done, I would appreciate a formula for that. I'm building the scrip开发者_StackOverflow社区t in php here.

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Just print all values from 0 to 2^24 and format it as hex with 6 digits...

long max = pow(2,24);
for(long i = 0; i < max; i++)
{
printf("%6x\n", i);
}

Something like that?

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for i = 0 to 16 million
    print i as hexa