18 lines
361 B
Python
18 lines
361 B
Python
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#!/usr/bin/env python3
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from math import factorial
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def main(k):
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n = 10
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ascend = binomial(n+k-1, k)
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descnd = sum(binomial(n+i-1, i) for i in range(1,k+1))
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repeat = n*k + 1 # why 1
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return ascend + descnd - repeat
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def binomial(n, k):
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return factorial(n) // (factorial(k)*factorial(n-k))
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#print(main(6))
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#print(main(10))
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print(main(100))
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