A040022 -id:A040022 - cp's OEIS frontend

A010483 Decimal expansion of square root of 28.

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

Offset: 1

N. J. A. Sloane

Continued fraction expansion is 5 followed by {3, 2, 3, 10} repeated. - Harry J. Smith, Jun 04 2009

			5.2915026221291811810032315072785208514205183661649003607366689184... - _Harry J. Smith_, Jun 04 2009

Harry J. Smith, Table of n, a(n) for n = 1..20000
John W. Layman, The Hankel Transform and Some of its Properties, J. Integer Sequences, 4 (2001), #01.1.5.
Index entries for algebraic numbers, degree 2.

Cf. A040022 Continued fraction. - Harry J. Smith, Jun 04 2009

RealDigits[N[Sqrt[28], 200]][[1]] (* Vladimir Joseph Stephan Orlovsky, Feb 22 2011 *)

{ default(realprecision, 20080); x=sqrt(28); for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b010483.txt", n, " ", d)); } \\ Harry J. Smith, Jun 04 2009

Equals 2*A010465. - R. J. Mathar, Jan 14 2021

A242703 Decimal expansion of sqrt(7)/2.

Original entry on oeis.org

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

Offset: 1

Alonso del Arte, May 20 2014

Absolute value of the imaginary part of any of the nontrivial divisors of 2 in O_Q(sqrt(-7)).
The incircle of a triangle with sides of lengths 4, 5, 6 units respectively has a radius of sqrt(7)/2.
With a different offset, decimal expansion of 5 * sqrt(7).
From Wolfdieter Lang, Nov 18 2017: (Start)
In a regular hexagon inscribed in a circle with a radius of 1 unit the three distinct distances between any vertex and the middle of the sides are 1/2, sqrt(7)/2 and sqrt(13)/2.
The continued fraction expansion of sqrt(7)/2 is 1, repeat(3, 10, 3, 2). The convergents are given in A294972/A294973. (End)

			1.32287565553229529525...

Iain Fox, Table of n, a(n) for n = 1..20000 (first 1000 terms from Ivan Panchenko)

Cf. A010527, A020837, A040022, A294972/A294973.

Mathematica
```
RealDigits[Sqrt[7]/2, 10, 100][[1]]
```

{ default(realprecision, 20080); x=sqrt(7)/2; for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b242703.txt", n, " ", d)); } \\ Iain Fox, Nov 18 2017

(1/2 - sqrt(-7)/2)(1/2 + sqrt(-7)/2) = 2.

Equals A010465/2. - R. J. Mathar, Feb 23 2021

cp's OEIS Frontend

A010483 Decimal expansion of square root of 28.

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