You are not logged in.
How many 20-digit numbers are such that the sum of their digits is even?
I could only figure out that there's at least
Last edited by muxdemux (2013-01-22 05:42:30)
That doesn't help, I knew that just that i keep losing count.
Hi;You do not have to do much counting. Spot the pattern works well here.I am getting 4.5 x 10 ^19 numbers.
Powered by FluxBB