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A071396
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Rounded total surface area of a regular octahedron with edge length n.
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5
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0, 3, 14, 31, 55, 87, 125, 170, 222, 281, 346, 419, 499, 585, 679, 779, 887, 1001, 1122, 1251, 1386, 1528, 1677, 1833, 1995, 2165, 2342, 2525, 2716, 2913, 3118, 3329, 3547, 3772, 4005, 4244, 4489, 4742, 5002, 5269, 5543, 5823, 6111, 6405, 6707, 7015, 7330
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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REFERENCES
| S. Selby, editor, CRC Basic Mathematical Tables, CRC Press, 1970, pp. 10-11.
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..10000
Eric Weisstein's World of Mathematics, Octahedron
Eric Weisstein's World of Mathematics, Platonic Solid
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FORMULA
| a(n) = round(2 * n^2 * sqrt(3))
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EXAMPLE
| a(3)=31 because round(2*3^2*sqrt(3))=round(18*1.73205...)=round(31.1769...)=31.
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PROG
| (PARI) for(n=0, 100, print1(round(2*n^2*sqrt(3)), ", "))
(MAGMA) [Round(2*n^2 * Sqrt(3)): n in [0..50]]; // Vincenzo Librandi, May 21 2011
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CROSSREFS
| Cf. A070169 (tetrahedron), A033581 (cube), A071397 (dodecahedron), A071398 (icosahedron), A071400 (volume of octahedron).
Sequence in context: A031049 A014696 A197944 * A032525 A197946 A130697
Adjacent sequences: A071393 A071394 A071395 * A071397 A071398 A071399
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KEYWORD
| easy,nonn
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AUTHOR
| Rick L. Shepherd (rshepherd2(AT)hotmail.com), May 23 2002
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