A157215 Decimal expansion of 18 - 5*sqrt(2).

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

Offset: 2

Author

Klaus Brockhaus, Feb 25 2009

Keywords

• cons
• nonn

Comments

lim_{n -> infinity} b(n)/b(n-1) = (18+5*sqrt(2))/(18-5*sqrt(2)) for n mod 3 = {1, 2}, b = A129544.

lim_{n -> infinity} b(n)/b(n-1) = (18+5*sqrt(2))/(18-5*sqrt(2)) for n mod 3 = {0, 2}, b = A157213.

Examples

			18 - 5*sqrt(2) = 10.92893218813452475599...
		

Links

• G. C. Greubel, Table of n, a(n) for n = 2..5001
• Index entries for algebraic numbers, degree 2

Crossrefs

Cf. A129544, A157213, A157214 (decimal expansion of 18+5*sqrt(2)), A157216 (decimal expansion of (18-5*sqrt(2))/(18+5*sqrt(2))).

Programs

Magma

[18 - 5*Sqrt(2)]; // G. C. Greubel, Nov 28 2017

Mathematica

RealDigits[18 - 5*Sqrt[2], 10, 50][[1]] (* G. C. Greubel, Nov 28 2017 *)

PARI

18 - 5*sqrt(2) \\ G. C. Greubel, Nov 28 2017