Sum of two cousins
Difficulty level:
The number 10 can be written in two ways as a sum of two prime numbers:
10 = 5 + 5
and
10 = 7 + 3
How many ways can the number 549 be written as a sum of two prime numbers?
Difficulty level:
The number 10 can be written in two ways as a sum of two prime numbers:
10 = 5 + 5
and
10 = 7 + 3
How many ways can the number 549 be written as a sum of two prime numbers?