A020847 - OEIS

A020847

Decimal expansion of 1/sqrt(90) = sqrt(10)/30.

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

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OFFSET

0,3

COMMENTS

sqrt(10)/3 = 1.054.. is the length of the shortest line segment needed to dissect the unit square into 6 regions with equal areas if all the line segments start at the same vertex of the square. - Wesley Ivan Hurt, May 18 2021

LINKS

Ivan Panchenko, Table of n, a(n) for n = 0..1000

FORMULA

Equals 0.1 * Sum_{k>=0} binomial(2*k,k)/40^k. - Amiram Eldar, Aug 04 2022

EXAMPLE

0.10540925533894597773329645148109061779065183797750...

MATHEMATICA

RealDigits[1/Sqrt[90], 10, 120][[1]] (* Harvey P. Dale, May 02 2012 *)

PROG

(PARI) 1/sqrt(90) \\ Amiram Eldar, Aug 04 2022

CROSSREFS

Sequence in context: A193035 A227966 A021653 * A128355 A361050 A325221

Adjacent sequences: A020844 A020845 A020846 * A020848 A020849 A020850

KEYWORD

nonn,cons

AUTHOR

N. J. A. Sloane.

STATUS

approved