Homework Statement
a) Show that the magic constant of an nth order normal magic square is n(n^2+1)/2.
b) Show that the center of a 3x3 must be occupied by the number 5.
c) Show that in a normal magic square of 3x3 the number 1 can never occur in a corner cell.
Homework Equations...
Homework Statement
Prove that the sum of the reciprocals of all divisors of a perfect number is equal to 2.
Homework Equations
Euclid's formula for perfect #'s
The Attempt at a Solution
I am so lost.
Homework Statement
Proof and show that in Euclid's formula for perfect numbers, n must be prime.
Homework Equations
(2^(n-1))((2^n)-1))
The Attempt at a Solution
I can show it by plugging in the number but I cannot prove it...any ideas?