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A099972 Write 1/sqrt(2) as a binary fraction; read this from left to right and whenever a 1 appears, note the integer formed by reading leftwards from that 1. 11
1, 5, 13, 45, 173, 8365, 73901, 204973, 467117, 991405, 5185709, 13574317, 80683181, 214900909, 1288642733, 3436126381, 7731093677, 16321028269, 33500897453, 67860635821, 136580112557, 686335926445, 1785847554221 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Harvey P. Dale, Table of n, a(n) for n = 0..1000

EXAMPLE

1/sqrt(2) = 0.7071067811865475244008443621048490392848359376885... = 0.10110101000001001111001100110011111110011101111001100100100001000101100101111101100010011011 in binary.

MATHEMATICA

d = 100; l = First[RealDigits[N[1/Sqrt[2], d], 2]]; Do[m = Take[l, n]; k = Length[m]; If[m[[k]] == 1, Print[FromDigits[Reverse[m], 2]]], {n, 1, d}] (* Ryan Propper, Aug 18 2005 *)

Module[{rd=RealDigits[1/Sqrt[2], 2, 50][[1]], pos}, pos=Flatten[Position[rd, 1]]; Table[ FromDigits[ Reverse[Take[rd, n]], 2], {n, pos}]] (* Harvey P. Dale, Jul 29 2013 *)

CROSSREFS

Cf. A010503, A099969, A099970, A099971, A099973, A099974.

Sequence in context: A147200 A147396 A320877 * A060050 A217892 A194639

Adjacent sequences:  A099969 A099970 A099971 * A099973 A099974 A099975

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Nov 13, 2004, based on correspondence from Artur Jasinski, Mar 25 2003

EXTENSIONS

More terms from Ryan Propper, Aug 18 2005

STATUS

approved

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Last modified July 16 04:26 EDT 2019. Contains 325064 sequences. (Running on oeis4.)