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A394107
Decimal expansion of the probability that three points uniformly and independently selected at random from the interior of an equilateral triangle form the vertices of an obtuse triangle.
2
7, 4, 8, 1, 9, 7, 2, 2, 3, 3, 4, 2, 0, 2, 2, 9, 3, 0, 0, 3, 5, 5, 1, 9, 7, 2, 0, 3, 5, 8, 1, 3, 7, 2, 8, 1, 9, 7, 9, 7, 0, 6, 3, 6, 8, 2, 0, 0, 0, 5, 6, 9, 5, 4, 2, 7, 4, 8, 4, 3, 0, 2, 7, 5, 0, 2, 0, 7, 0, 4, 5, 0, 0, 9, 7, 1, 9, 3, 3, 6, 6, 0, 6, 3, 1, 3, 1, 2, 4, 6, 8, 1, 4, 9, 1, 9, 4, 7, 1, 6, 8, 7, 6, 3, 8
OFFSET
0,1
LINKS
Dominik Beck, The Probability that a Random Triangle in a Cube is Obtuse, arXiv:2501.11611 [math.MG], 2025.
Dominik Beck, Random polytopes, doctoral thesis, Mathematical Institute of Charles University, Prague, 2025.
FORMULA
Equals 25/4 + Pi/(12*sqrt(3)) + (393/10)*log(sqrt(3)/2).
EXAMPLE
0.748197223342022930035519720358137281979706368200056...
MATHEMATICA
RealDigits[25/4 + Pi/(12*Sqrt[3]) + (393/10)*Log[Sqrt[3]/2], 10, 120][[1]]
PROG
(PARI) 25/4 + Pi/(12*sqrt(3)) + (393/10)*log(sqrt(3)/2)
CROSSREFS
Cf. A244977.
Sequence in context: A303133 A389398 A195384 * A021576 A222183 A010509
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Mar 10 2026
STATUS
approved