math question
Message posted by marilyn (via 206.141.213.137) on August 16, 2001 at 10:40 PM (ET)

I would like to know if someone can tell me. If you have the numbers 0-10, what are the combinations that can be made that are at least 4 to 10 numbers in length. can you name them all or where can i go to find them.

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Re: math question
Message posted by Jack Tomsky (via 208.249.113.130) on August 17, 2001 at 7:19 PM (ET)

Sum C(11,j), where the sum is over j = 4, ..., 11 and

C(11,j) = 11!/[j! (11-j)!]

To list all the combinations, just arrange them in lexigographic order.

Re: math question
Message posted by Tomi Owens (via 154.32.143.161) on August 21, 2001 at 7:27 PM (ET)

Largest 10 digit number: 9,999,999,999
Smallest 4 digit number: 1,000

You just want all the numbers from 1,000 to 9,999,999,999 (inclusive). There are (9,999,999,999 - 1000) + 1 of these:
= 9,999,998,999 + 1
= 9,999,999,000.