A334849 Decimal expansion of circumference of 4 x^2 + 9 y^2 = 36.

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

Offset: 2

Author

Clark Kimberling, Jun 15 2020

Keywords

• nonn
• cons
• easy

Examples

			arclength = 15.8654395892905897913316630277830724967300828483...
		

Crossrefs

Cf. A333202, A334848.

Programs

Mathematica

s = Integrate[Sqrt[D[ 3 Cos[t], t]^2 + D[2 Sin[t], t]^2], {t, 0, 2 Pi}]
r = N[s, 200]
RealDigits[r][[1]]

Formula

arclength = 8 E(-5/4), where E = complete elliptic integral.