Tattah's youngest brother, Tuftuf, is new to programming.

Since his older brother is such a good programmer, his biggest dream is to outshine him. Tuftuf is a student at the German University in Cairo (GUC) where he learns to write programs in Gava.

Today, Tuftuf was introduced to Gava's unsigned integer datatypes. Gava has n unsigned integer datatypes of sizes (in bits) a1,a2,... an. The i-th datatype have size ai bits, so it can represent every integer between 0 and 2ai-1 inclusive.

Tuftuf is thinking of learning a better programming language. If there exists an integer x, such that x fits in some type i (in ai bits) and x \cdot x does not fit in some other type j (in aj bits) where ai \lt aj, then Tuftuf will stop using Gava.

Your task is to determine Tuftuf's destiny.

The first line contains integer n (2 \le n \le 105) - the number of Gava's unsigned integer datatypes' sizes. The second line contains a single-space-separated list of n integers (1 \le ai \le 109) - sizes of datatypes in bits. Some datatypes may have equal sizes.

Print "YES" if Tuftuf will stop using Gava, and "NO" otherwise.

In the second example, x=7 (1112) fits in 3 bits, but x2=49 (1100012) does not fit in 4 bits.