A381153 Decimal expansion of the isoperimetric quotient of a regular heptagon.

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

Offset: 0

Author

Paolo Xausa, Feb 15 2025

Keywords

• nonn
• cons
• easy

Comments

For the definition of isoperimetric quotient, see A381152.

Examples

			0.93194062349909574595222630089422754574528525154715...
		

Links

• Paolo Xausa, Table of n, a(n) for n = 0..10000
• Eric Weisstein's World of Mathematics, Isoperimetric Quotient.
• Wikipedia, Isoperimetric inequality.

Crossrefs

Cf. A178817, A343058.

Cf. isoperimetric quotient of other regular polygons: A073010 (triangle), A003881 (square), A381152 (pentagon), A093766 (hexagon), A196522 (octagon), A381154 (9-gon), A381155 (10-gon), A381156 (11-gon), A381157 (12-gon).

Programs

Mathematica

First[RealDigits[Pi/(7*Tan[Pi/7]), 10, 100]]

Formula

Equals Pi/(7*tan(Pi/7)) = Pi/(7*A343058).

Equals (4/49)*Pi*A178817.