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Prime Numbers
2, 3, 5, 7, ... The set of prime numbers is the alphabet of mathematics that allows us to communicate across the universe.
\[2^{2014}+ 1007^4\] Is this sum equal to a prime number?
by
Joshua Ong
Mr. White is an approximately forty years old father with 4 sons of distinct ages. Writing his age 3 times in succession, we get a 6-digit number that is equal to the product of his age, his wife's age and his 4 sons' ages.
Give the sum of his wife's age and all 4 sons' ages.
by
Drop TheProblem
A three-digit number \(N\) has first digit \(a (\neq 0)\), second digit \(b\) and third digit \(c\). \(N = b(10c + b)\) where \(b\) and \((10c + b)\) are primes. Find \(N\).
by
Sharky Kesa
How many integers from \(1\) to \(100\) inclusive can be written as the product of two (not necessarily distinct) primes?
If you can find a computer science or combinatorics approach, post your solution!
by
Finn Hulse
