A088543 Decimal expansion of sqrt(15)/2.

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

Offset: 1

Author

Christopher M. Tomaszewski (cmt1288(AT)comcast.net), Nov 16 2003

Keywords

• cons
• nonn

Comments

This is the ratio of the base of an isosceles triangle to its height when the other two sides are each equal to twice the base.

Exradius opposite the side of length 3 of the obtuse scalene triangle with sides of lengths 2, 3 and 4, the scalene triangle with least integer side lengths. See formulas in the Weisstein link. - Rick L. Shepherd, May 14 2008

Examples

			1.93649167310370844258963269989119980541646085264579541329378688305674154596...
		

Links

• Daniel Starodubtsev, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Exradius.
• Index entries for algebraic numbers, degree 2

Crossrefs

Cf. A010527.

Cf. A140239, A140246, A140247, A140248, A140249, A010472.

Programs

Mathematica

First[RealDigits[Sqrt[15]/2, 10, 100]] (* Paolo Xausa, Jun 18 2024 *)

Formula

sqrt(15)/2 = A010472/2 = A140249/3. - Rick L. Shepherd, May 14 2008

Extensions

More terms from Rick L. Shepherd, May 14 2008