# It was proposed by Christian Goldbach that every odd composite number can be written as the sum of a prime and twice a square. 
# 9 = 7 + 2×12
15 = 7 + 2×22
21 = 3 + 2×32
25 = 7 + 2×32
27 = 19 + 2×22
33 = 31 + 2×12 
# It turns out that the conjecture was false. 
# What is the smallest odd composite that cannot be written as the sum of a prime and twice a square? 
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