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A213255
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2^(n-1) - floor((2^(n-1) - 1)/(n-1)).
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1
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1, 3, 6, 13, 26, 54, 110, 225, 456, 922, 1862, 3755, 7562, 15214, 30584, 61441, 123362, 247581, 496694, 996148, 1997288, 4003654, 8023886, 16078166, 32212255, 64527754, 129246702, 258848476, 518358122, 1037950430, 2078209982, 4160749569, 8329633544
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OFFSET
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2,2
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COMMENTS
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Lower bounds of the decycling numbers of n-cubes for n >= 9.
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LINKS
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FORMULA
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a(n) = 2^(n-1) - floor((2^(n-1) - 1)/(n-1)).
a(n) = ceiling(2^(n-1) - (2^(n-1) - 1)/(n-1)).
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EXAMPLE
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a(8) = 110 because 2^7 - (2^7 - 1)/7 = 109.8571428571....
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MATHEMATICA
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Table[Ceiling[2^(n - 1) - (2^(n - 1) - 1)/(n - 1)], {n, 2, 34}]
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PROG
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(Magma) [Ceiling(2^(n-1)-(2^(n-1)-1)/(n-1)) : n in [2..34]]
(PARI) for(n=2, 34, print1(ceil(2^(n-1)-(2^(n-1)-1)/(n-1)), ", "))
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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