This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A380703 #8 Jan 30 2025 17:44:07 %S A380703 2,0,4,5,5,3,5,8,3,8,3,4,9,1,6,7,7,4,9,4,0,0,9,1,6,8,1,7,6,3,8,2,4,5, %T A380703 5,2,7,2,3,7,7,4,4,6,7,2,0,5,6,6,9,7,1,8,6,9,8,3,8,4,7,7,1,4,5,8,7,1, %U A380703 3,7,5,3,5,1,9,3,2,3,8,0,8,7,8,4,8,1,6,4,1,9 %N A380703 Decimal expansion of the obtuse vertex angle, in radians, in a (small) triakis octahedron face. %H A380703 Paolo Xausa, <a href="/A380703/b380703.txt">Table of n, a(n) for n = 1..10000</a> %H A380703 Wikipedia, <a href="https://en.wikipedia.org/wiki/Triakis_octahedron">Triakis octahedron</a>. %F A380703 Equals arccos(1/4 - sqrt(2)/2) = arccos(1/2 + A010503). %F A380703 Equals Pi - 2*A380702. %e A380703 2.045535838349167749400916817638245527237744672... %t A380703 First[RealDigits[ArcCos[1/4 - Sqrt[2]/2], 10, 100]] %Y A380703 Cf. A380702 (face obtuse angles). %Y A380703 Cf. A010503, A378351, A378352, A378353, A378354. %K A380703 nonn,cons,easy %O A380703 1,1 %A A380703 _Paolo Xausa_, Jan 30 2025