18 lines
282 B
Python
18 lines
282 B
Python
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#!/usr/bin/env python3
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from math import factorial
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def bin(n, k):
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if n < 0:
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return 0
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if n < k:
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return 0
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return factorial(n) // (factorial(n-k) * factorial(k))
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n = 12
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ms = 0
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for k in range(0, n//2 +1):
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ms += bin(n, 2*k) * bin(2*k-1, k+1)
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print(ms)
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