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A130082
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Smallest number whose eighth power has at least n digits.
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1
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1, 2, 2, 3, 4, 5, 6, 8, 10, 14, 18, 24, 32, 43, 57, 75, 100, 134, 178, 238, 317, 422, 563, 750, 1000, 1334, 1779, 2372, 3163, 4217, 5624, 7499, 10000, 13336, 17783, 23714, 31623, 42170, 56235, 74990, 100000, 133353, 177828, 237138, 316228, 421697
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OFFSET
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1,2
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COMMENTS
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Powers of eighth root of 10 rounded up.
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LINKS
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FORMULA
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a(n) = ceiling(10^((n-1)/8)).
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EXAMPLE
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9^8 = 43046721 has eight digits, 10^8 = 100000000 has nine digits, hence a(9) = 10.
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MATHEMATICA
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PROG
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(Magma) [ Ceiling(Root(10^(n-1), 8)): n in [1..46] ];
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CROSSREFS
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Cf. A011557 (powers of 10), A017936 (smallest number whose square has n digits), A018005 (smallest number whose cube has n digits), A018074 (smallest number whose fourth power has n digits), A018143 (smallest number whose fifth power has n digits), A130080 to A130084 (smallest number whose sixth ... tenth power has n digits).
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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