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A060377
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Pepin's test numbers.
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1
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OFFSET
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0,1
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COMMENTS
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LINKS
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FORMULA
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a(n) = 3^((F(n)-1)/2) where F(n) is a Fermat number (A000215).
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EXAMPLE
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a(1) = 3^((F(1)-1)/2) = 3^((5-1)/2) = 3^2 = 9.
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PROG
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(Python)
def a(n): return 3**(2**(2**n-1))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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