Problem C. 1273. (February 2015)

C. 1273. Prove that \(\displaystyle 3^{4n}+4\cdot 7^{4k}\) is divisible by 5 for all \(\displaystyle n,k\in \mathbb{N}\).

(5 pont)

Deadline expired on March 10, 2015.

Statistics:

144 students sent a solution.
5 points:	54 students.
4 points:	45 students.
3 points:	37 students.
2 points:	5 students.
1 point:	1 student.
0 point:	2 students.

Problems in Mathematics of KöMaL, February 2015