Talk:Sphenomegacorona

Latest comment: 4 years ago by OfficialURL in topic Volume of sphenomegacorona of unit edge length

Volume of sphenomegacorona of unit edge length edit

WolframAlpha gives its volume as 1.94833, but my calculations in both Mathematica and GeoGebra show that the actual number, rounded to 5 digits, should instead be 1.94811. If anyone wants to check, here is my Mathematica code, based on Timofeenko's paper on the references.

k := Root[-23 - 56 x + 200 x^2 + 304 x^3 - 776 x^4 + 240 x^5 + 2000 x^6 - 5584 x^7 - 3384 x^8 + 17248 x^9 + 2464 x^10 - 24576 x^11 + 1568 x^12 + 17216 x^13 - 3712 x^14 - 4800 x^15 + 1680 x^16, 2]
v := {{0, 1, 2 Sqrt[1 - k^2]}, {0, -1, 2 Sqrt[1 - k^2]}, {2 k, 1, 0}, {2 k, -1, 0}, {-2 k, 1, 0}, {-2 k, -1, 0}, {0, Sqrt[(3 - 4 k^2)/(1 - k^2)] + 1, (1 - 2 k^2)/Sqrt[1 - k^2]}, {0, -Sqrt[(3 - 4 k^2)/(1 - k^2)] - 1, (1 - 2 k^2)/Sqrt[1 - k^2]}, {1, 0, -Sqrt[2 + 4 k - 4 k^2]}, {-1, 0, -Sqrt[2 + 4 k - 4 k^2]}, {0, (Sqrt[3 - 4 k^2] (2 k^2 - 1))/((k^2 - 1) Sqrt[1 - k^2]) + 1, (2 k^4 - 1)/(1 - k^2)^(3/2)}, {0, -(Sqrt[3 - 4 k^2] (2 k^2 - 1))/((k^2 - 1) Sqrt[1 - k^2]) - 1, (2 k^4 - 1)/(1 - k^2)^(3/2)}}
f := {{2, 4, 3, 1}, {5, 1, 2, 6}, {4, 9, 3}, {3, 9, 11}, {1, 7, 3}, {3, 7, 11}, {7, 1, 5}, {5, 7, 11}, {5, 10, 11}, {5, 10, 6}, {11, 10, 9}, {2, 6, 8}, {2, 4, 8}, {8, 12, 6}, {4, 8, 12}, {6, 12, 10}, {12, 10, 9}, {12, 4, 9}}
N[Volume[Polyhedron[v, f]]/8, 6]

I'm currently proposing the sequence of digits to the OEIS, so it can be used as a reference. – OfficialURL (talk) 14:48, 13 April 2020 (UTC)Reply

Reference added to A334114. – OfficialURL (talk) 13:45, 15 April 2020 (UTC)Reply