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A010532 Decimal expansion of square root of 80. 9
8, 9, 4, 4, 2, 7, 1, 9, 0, 9, 9, 9, 9, 1, 5, 8, 7, 8, 5, 6, 3, 6, 6, 9, 4, 6, 7, 4, 9, 2, 5, 1, 0, 4, 9, 4, 1, 7, 6, 2, 4, 7, 3, 4, 3, 8, 4, 4, 6, 1, 0, 2, 8, 9, 7, 0, 8, 3, 5, 8, 8, 9, 8, 1, 6, 4, 2, 0, 8, 3, 7, 0, 2, 5, 5, 1, 2, 1, 9, 5, 9, 7, 6, 5, 7, 6, 5, 7, 6, 3, 3, 5, 1, 5, 1, 2, 9, 0, 9, 9, 8, 7, 8, 0, 3 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Continued fraction expansion is 8 followed by {1, 16} repeated. - Harry J. Smith, Jun 09 2009

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..20000

FORMULA

From Amiram Eldar, Aug 02 2020: (Start)

Equals 10 * 2/sqrt(5) = 10 * Sum_{k>=0} (-1)^k * binomial(2*k,k)/16^k.

Equals 8 + Sum_{k>=0} (-1)^k * binomial(2*k,k)/((k+1) * 16^k). (End)

EXAMPLE

8.944271909999158785636694674925104941762473438446102897083588981642083... - Harry J. Smith, Jun 09 2009

MATHEMATICA

RealDigits[Sqrt[80], 10, 120][[1]] (* Harvey P. Dale, Oct 20 2011 *)

PROG

(PARI) { default(realprecision, 20080); x=sqrt(80); for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b010532.txt", n, " ", d)); } \\ Harry J. Smith, Jun 09 2009

CROSSREFS

Cf. A040071 (continued fraction). - Harry J. Smith, Jun 09 2009

Sequence in context: A021532 A188638 A244664 * A317864 A335963 A243267

Adjacent sequences:  A010529 A010530 A010531 * A010533 A010534 A010535

KEYWORD

nonn,cons,changed

AUTHOR

N. J. A. Sloane

EXTENSIONS

Final digits of sequence corrected using the b-file. - N. J. A. Sloane, Aug 30 2009

STATUS

approved

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Last modified August 7 11:08 EDT 2020. Contains 336275 sequences. (Running on oeis4.)