Problem 52497. Easy Sequences 3: Prime 44-number Squares
The positive integers 62 and 238 are related. Their squares (3844 and 56,644) both end in '44'. In fact, 62 and 238 are the 3rd and 10th positive integers, respectively, that have this property. We will call a positive number whose square ends in '44' as a "44-number".
If 'x' is the nth 44-number, we define the function 'S(n)' to be the sum of the digits of 'x^2' but excluding the ending '44'. So in the cases above, S(3) = 11 and S(10) = 17. We noticed that both of these sums are primes.We define 'P(n)' as the number of prime S(n)'s among the first 'n' 44-numbers. Write a function that returns P(n), given that P(3) = 2 and P(10) = 5.
Solution Stats
Problem Comments
Solution Comments
Show commentsProblem Recent Solvers25
Suggested Problems
-
9982 Solvers
-
Project Euler: Problem 9, Pythagorean numbers
1142 Solvers
-
1404 Solvers
-
357 Solvers
-
Put two time series onto the same time basis
322 Solvers
More from this Author116
Problem Tags
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!