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A349579
Decimal expansion of the 4-dimensional Steinmetz solid formed by the intersection of 4 unit-diameter 4-dimensional cylinders whose axes are mutually orthogonal and intersect at a single point.
3
3, 2, 9, 6, 6, 1, 9, 1, 3, 6, 2, 4, 2, 2, 5, 0, 3, 9, 7, 9, 5, 4, 0, 4, 7, 4, 8, 6, 7, 7, 5, 8, 7, 5, 7, 1, 3, 4, 3, 3, 4, 5, 1, 9, 3, 3, 3, 1, 6, 2, 1, 3, 6, 0, 5, 7, 0, 3, 3, 9, 9, 0, 0, 0, 0, 2, 9, 4, 0, 7, 8, 9, 2, 8, 7, 6, 1, 0, 2, 4, 1, 3, 1, 1, 0, 1, 1, 2, 6, 2, 3, 6, 4, 5, 0, 9, 0, 1, 3, 9, 5, 9, 2, 5, 2
OFFSET
0,1
COMMENTS
The constant given by Hildebrand et al. (2012) and Kong et al. (2013) is for unit-radius cylinders, and is thus larger by a factor of 2^4. The constant here, for a unit-diameter cylinders, is analogous to the 3-dimensional case given by Moore (1974).
LINKS
A. J. Hildebrand, Lingyi Kong, Abby Turner and Ananya Uppal, Applications of n-dimensional Integrals: Random Points, Broken Sticks and Intersecting Cylinders, Illinois Geometry Lab Project Report, University of Illinois at Urbana-Champaign, December 11, 2012.
Lingyi Kong, Luvsandondov Lkhamsuren, Abigail Turner, Aananya Uppal and A. J. Hildebrand, Intersecting Cylinders: From Archimedes and Zu Chongzhi to Steinmetz and Beyond, Illinois Geometry Lab Project Report, University of Illinois at Urbana-Champaign, April 25, 2013.
Moreton Moore, Symmetrical Intersections of Right Circular Cylinders, The Mathematical Gazette, Vol. 58, No. 405 (1974), pp. 181-185.
FORMULA
Equals 3 * (Pi/4 - arctan(sqrt(2))/sqrt(2)).
EXAMPLE
0.32966191362422503979540474867758757134334519333162...
MATHEMATICA
RealDigits[3 * (Pi/4 - ArcTan[Sqrt[2]]/Sqrt[2]), 10, 100][[1]]
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Nov 22 2021
STATUS
approved