85 lines
1.6 KiB
Python
85 lines
1.6 KiB
Python
'''
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cache = {}
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def binomcoeffb(n,k):
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nom = 1
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denum = 1
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for i in range(n-k):
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nom *= (n-i)
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denum *= (i+1)
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v = nom//denum
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cache[(n,k)] = v
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return v
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def binomcoeffc(n,k):
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if (n,k) in cache:
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return cache[(n,k)]
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if n == k or k == 0:
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return 1
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v = binomcoeffc(n-1,k-1) + binomcoeffc(n-1,k)
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cache[(n,k)] = v
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return v
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def binomcoeff(n,k):
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try:
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v = binomcoeffc(n,k)
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except RuntimeError:
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v = binomcoeffb(n,k)
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return v
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def binomcoeffi():
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l = [1,2,1]
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i = 3
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yield (i,l[1:-1])
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while True:
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i += 1
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nl = [1]
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for j in range(len(l)-1):
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nl.append( l[j]+l[j+1] )
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nl.append(1)
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l = nl
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yield (i,l[1:-1])
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def is_prime(n):
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if n <= 1:
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return False
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for n
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bc = binomcoeff(n,k)
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r = bc % n
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# print("%d %% %d = %d" % (bc,n,r))
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if r != 0:
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return False
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return True
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'''
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class PrimeGenerator:
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def __init__(self):
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self.coeffs = [1,1]
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self.prime = 1
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def nextPrime(self):
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self.step()
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while not self.check():
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self.step()
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return self.prime
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def step(self):
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l = [1]
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for j in range(len(self.coeffs)-1):
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l.append(self.coeffs[j] + self.coeffs[j+1])
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l.append(1)
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self.coeffs = l
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self.prime += 1
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def check(self):
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for i in range(1,len(self.coeffs)//2+1):
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if self.coeffs[i] % self.prime != 0:
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return False
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return True
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pg = PrimeGenerator()
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for i in range(10001):
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print("%d: %d" % (i,pg.nextPrime()) )
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