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A070169
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Rounded total surface area of a regular tetrahedron with edge length n.
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9
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0, 2, 7, 16, 28, 43, 62, 85, 111, 140, 173, 210, 249, 293, 339, 390, 443, 501, 561, 625, 693, 764, 838, 916, 998, 1083, 1171, 1263, 1358, 1457, 1559, 1665, 1774, 1886, 2002, 2122, 2245, 2371, 2501, 2634, 2771, 2912, 3055, 3203, 3353, 3507, 3665, 3826, 3991
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OFFSET
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0,2
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COMMENTS
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a(n) is the integer k that minimizes |k/n^2 - sqrt(3)|. - Clark Kimberling, Oct 11 2017
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REFERENCES
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S. Selby, editor, CRC Basic Mathematical Tables, CRC Press, 1970, pp. 10-11.
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LINKS
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FORMULA
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a(n) = round(n^2 * sqrt(3)).
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EXAMPLE
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a(3)=16 because round(3^2*sqrt(3)) = round(9*1.73205...) = round(15.5884...) = 16.
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MATHEMATICA
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PROG
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(PARI) for(n=0, 100, print1(round(n^2*sqrt(3)), ", "))
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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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