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A class Ive had in my snippets for awhile that can generate prime, perfect and fibonacci sequences as well as check whether or not a supplied value is any of them.

Python, 164 lines
 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166``` ```""" A Fun Widget Class For Playing With Prime, Perfect and Fibonacci Numbers """ class PrimePerFib: def __init__(self): pass def Factor(self, n): yield 1 i = 2 limit = n**0.5 while i <= limit: if n % i == 0: yield i n = n / i limit = n**0.5 else: i += 1 if n > 1: yield n def PrimeFactor(self, n): for x in self.Factor(n): if x != 1 and x != n: return False return True """ A Hybrid Sieve of Atkin, without all the quadratics and keeping of sequences allows for generating blocks of primes """ def PrimeGen(self, count, start): c = 0 base = [2,3,5] start = int(round(start)) n = (2,max(2,(start,start+1)[start % 2 == 0]))[start != 2] while c < count: if n in base: yield n if n == 2: n+=1; c+=1; continue else: n+=2; c+=1; continue if not [m for m in base if (n%60) % m == 0 ]: if n % n**0.5 != 0: if self.PrimeFactor(n): c += 1 yield n n += 2 def PrimeGet(self, num): r = self.PrimeGen(1,num).next() return r def IsPrime(self, num): return (False,True)[self.PrimeGet(num)==num] def NextPrime(self, num): return (self.PrimeGet(num),self.PrimeGet(num+1))[self.IsPrime(num)] def PerfectGen(self, count, start=0): output = 0 prime = 0 while output < count: prime = self.NextPrime(prime) mPrime = 2**prime - 1 if not self.IsPrime(mPrime): continue pN =(2**(prime-1))*(2**prime - 1) if pN >= start: output += 1 yield pN def PerfectGet(self, num): return self.PerfectGen(1,num).next() def IsPerfect(self, num): return (False,True)[self.PerfectGet(num)==num] def NextPerfect(self, num): return (self.PerfectGet(num),self.PerfectGet(num+1))[self.IsPerfect(num)] def FibonacciGen(self, count, start=0): output = 0 fib = [0,1] while output < count: fN = fib[len(fib)-1] + fib[len(fib)-2] fib.append(fN) fib.pop(0) if fN >= start: output += 1 yield fN def FibonacciGet(self, num): return self.FibonacciGen(1,num).next() def IsFibonacci(self, num): return (False,True)[self.FibonacciGet(num)==num] def NextFibonacci(self, num): return (self.FibonacciGet(num),self.FibonacciGet(num+1))[self.IsFibonacci(num)] if __name__ == '__main__': PPF = PrimePerFib() ########################################################################## #Prime Numbers print "What Prime Number Comes After 56? ",PPF.NextPrime(56) print "Is 333 A Prime Number? ",PPF.IsPrime(333) Primes = [] for Prime in PPF.PrimeGen(10,42): Primes.append(Prime) print "Generated Primes: ",Primes,"\n\n" ########################################################################## #Perfect Numbers #Need Some Horsepower In Your Machine To Play With These print "What Perfect Number Comes After 9685 ",PPF.NextPerfect(9685) print "Is 8128 A Perfect Number ",PPF.IsPerfect(8128) Perfects = [] for Perfect in PPF.PerfectGen(8, 0): Perfects.append(Perfect) print "Generated Perfect Numbers ",Perfects,"\n\n" ########################################################################## #Fibonacci Numbers print "What is the Next Fibonacci Number After 5 ? ",PPF.NextFibonacci(5) print "Is 16 A Fibonacci Number? ",PPF.IsFibonacci(16) Fibonaccis = [] for Fibonacci in PPF.FibonacciGen(42, 10): Fibonaccis.append(Fibonacci) print "Generated Fibonacci Numbers ",Fibonaccis ```
 Created by AJ. Mayorga on Mon, 17 May 2010 (MIT)

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