情趣生活

情趣生活 => 灵机一动 => Topic started by: MrPuzzle on 九月 03, 2004, 08:41:39 am

Title: Long digits
Post by: MrPuzzle on 九月 03, 2004, 08:41:39 am
Let A be the sum of the decimal digits of 4444^4444, and B be the sum of the decimal digits of A. Find the sum of the decimal digits of B.
Title: 7
Post by: sean on 九月 03, 2004, 03:33:15 pm
A< 9(4444*4+1)<9*10^5,
B<9*6=54
C<14.

4444^4444=7 mod 9