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A004539 Expansion of sqrt(2) in base 2. 10
1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

R. L. Graham and H. O. Pollak, Note on a nonlinear recurrence related to sqrt(2), Mathematics Magazine, Volume 43, Pages 143-145, 1970. Zbl 201.04705.

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

D. Bailey et al., On the binary expansions of algebraic numbers

Richard Isaac, On the simple normality to base 2 of the square root of s, for s not a perfect square.

Jason Kimberley, Index of expansions of sqrt(d) in base b

Thomas Stoll, A fancy way to obtain the binary digits of 759250125 sqrt{2}, (2009),  Amer. Math. Monthly, 117 (2010), 611-617.

Eric Weisstein's World of Mathematics, Wolfram's Iteration

Eric Weisstein's World of Mathematics, Pythagoras's Constant

MATHEMATICA

N[Sqrt[2], 200]; RealDigits[%, 2]

PROG

(bc) obase=2 scale=200 sqrt(2)

(Haskell)

a004539 n = a004539_list !! (n-1)

a004539_list = w 2 0 where

   w x r = bit : w (4 * (x - (4 * r + bit) * bit)) (2 * r + bit)

     where bit = head (dropWhile (\b -> (4 * r + b) * b < x) [0..]) - 1

-- Reinhard Zumkeller, Dec 16 2013

CROSSREFS

Cf. A002193 (decimal version), A233836 (run lengths of 0s and 1s).

Sequence in context: A129360 A129372 A169591 * A023960 A129686 A104974

Adjacent sequences:  A004536 A004537 A004538 * A004540 A004541 A004542

KEYWORD

nonn,base,cons

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified September 18 17:06 EDT 2014. Contains 246924 sequences.