In: Advanced Math
Prove that for any integer n the expression
n7/7 + n5/5 + 23n/35
is whole integer.
(Hint: Note that the problem can be state in a following equivalent
form: 35 | (5n7 +7n5 +23n);
even further, by the previews theorem, it would be enough to show
that (5n7 + 7n5 + 23n) is
divisible by 5 and 7.)