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Topic review (newest first)
- cooljackiec
- 2013-01-23 11:02:13
Thank you
- bobbym
- 2013-01-22 12:24:26
Hi;
You do not have to do much counting. Spot the pattern works well here.
I am getting 4.5 x 10 ^19 numbers.
- cooljackiec
- 2013-01-22 08:25:37
That doesn't help, I knew that just that i keep losing count.
- muxdemux
- 2013-01-22 05:42:14
I could only figure out that there's at least
.- cooljackiec
- 2013-01-22 04:13:22
How many 20-digit numbers are such that the sum of their digits is even?