A377995 Decimal expansion of the dihedral angle, in radians, between square and pentagonal faces in a (small) rhombicosidodecahedron.

2, 5, 8, 8, 0, 1, 8, 2, 9, 4, 6, 9, 2, 7, 4, 7, 9, 8, 6, 9, 5, 4, 1, 1, 0, 6, 5, 3, 1, 9, 0, 2, 3, 4, 3, 6, 4, 1, 6, 2, 1, 4, 5, 5, 7, 6, 6, 7, 4, 3, 8, 9, 4, 9, 7, 6, 3, 6, 6, 7, 4, 9, 8, 8, 5, 9, 0, 9, 6, 1, 2, 3, 6, 7, 9, 7, 5, 2, 7, 6, 0, 1, 6, 2, 1, 3, 2, 6, 2, 6

Offset: 1

Author

Paolo Xausa, Nov 15 2024

Keywords

• nonn
• cons
• easy

Comments

Also the dihedral angle, in radians, between square and 10-gonal faces in a truncated icosidodecahedron (great rhombicosidodecahedron).

Examples

			2.588018294692747986954110653190234364162145576674...
		

Links

• Eric Weisstein's World of Mathematics, Great Rhombicosidodecahedron.
• Eric Weisstein's World of Mathematics, Small Rhombicosidodecahedron.

Crossrefs

Cf. A242671, A377996.

Programs

Mathematica

First[RealDigits[ArcCos[-Sqrt[(5 + Sqrt[5])/10]], 10, 100]] (* or *)
First[RealDigits[Min[PolyhedronData["Rhombicosidodecahedron", "DihedralAngles"]], 10, 100]]

Formula

Equals arccos(-sqrt((5 + sqrt(5))/10)) = arccos(-sqrt(A242671)).