Given a positive integer n and if 1 plus 2 times n exactly divides 1 plus 2 raised to the power n, then n is said to be a Curzon number.

Write a function that determines whether a number is a Curzon number or not.

Examples

isCurzon(5) ➞ true
// 2 ** 5 + 1 = 33
// 2 * 5 + 1 = 11
// 33 is a multiple of 11

isCurzon(10) ➞ false
// 2 ** 10 + 1 = 1025
// 2 * 10 + 1 = 21
// 1025 is not a multiple of 21

isCurzon(14) ➞ true
// 2 ** 14 + 1 = 16385
// 2 * 14 + 1 = 29
// 16385 is a multiple of 29

Notes

• Use BigInteger or BigDecimal classes to deal with extremely big numbers.