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A371239
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Squarefree numbers that are zeroless in base 3 (A032924).
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3
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1, 2, 5, 7, 13, 14, 17, 22, 23, 26, 41, 43, 53, 67, 70, 71, 77, 79, 122, 130, 131, 133, 134, 149, 151, 157, 158, 161, 202, 203, 205, 206, 211, 214, 215, 229, 230, 233, 238, 239, 241, 365, 367, 373, 374, 377, 391, 394, 395, 401, 403, 445, 446, 449, 454, 455, 457
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OFFSET
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1,2
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COMMENTS
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The relative asymptotic density of this sequence within the zeroless numbers in base 3 is 27/(4*Pi^2) = 1/A214549 = 0.683917... (Banks and Shparlinski, 2004).
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LINKS
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MATHEMATICA
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Select[Range[500], !MemberQ[IntegerDigits[#, 3], 0] && SquareFreeQ[#] &]
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PROG
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(PARI) is(n) = vecmin(digits(n, 3)) > 0 && issquarefree(n);
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CROSSREFS
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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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