Making Strings

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You are given N. You have to count the number of binary strings (consists of only '0' and '1') of length 2*N such that the number of '1's in first string of length N is double of the number of '1's in second string of length N. Print the answer modulo 109+7. Input First line contains T, the number of test cases. Each test case consists of one integer N. Output For each test case print require

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solution.cppC++17

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