A099971 Write (sqrt(5)-1)/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.

1, 9, 25, 57, 121, 1145, 3193, 11385, 27769, 60537, 191609, 453753, 978041, 2026617, 10415225, 27192441, 94301305, 228519033, 496954489, 2644438137, 11234372729, 28414241913, 62773980281, 131493457017, 268932410489, 543810317433

Offset

0,2

Links

Table of n, a(n) for n=0..25.

Example

(sqrt(5)-1)/2 = 0.618033988749894848204586834365638117720309179805762862135... = 0.100111100011011101111001101110010111111101001010011111000001010111110011... in binary.

Mathematica

d = 100; l = First[RealDigits[N[(Sqrt[5]-1)/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 *)

Crossrefs

Cf. A094214, A099969, A099970, A099972, A099973, A099974.

Sequence in context: A304033 A048490 A113828 * A124702 A113829 A147338

Adjacent sequences: A099968 A099969 A099970 * A099972 A099973 A099974

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