A099974 - OEIS

%I #13 Nov 17 2018 21:24:19

%S 1,5,13,141,653,1677,3725,20109,544397,2641549,6835853,15224461,

%T 32001677,65556109,132664973,266882701,803753613,1877495437,

%U 4024979085,8319946381,16909880973,51269619341,601025433229,1700537061005

%N Write log(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.

%e log(2) = 0.69314718055994530941723212145817656807550013436025525412... = 0.1011000101110010000101111111011111010001110011110111100110101011110010011110... in binary.

%t d = 100; l = First[RealDigits[N[Log[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 17 2005 *)

%t Module[{nn=50,l2},l2=RealDigits[Log[2],2,nn][[1]];Table[FromDigits[ Reverse[ Take[ l2,n]],2],{n,nn}]]//Union (* _Harvey P. Dale_, Mar 29 2016 *)

%Y Cf. A002162, A099969, A099970, A099971, A099972, A099973.

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_, Nov 13, 2004, based on correspondence from _Artur Jasinski_, Mar 25 2003

%E More terms from _Ryan Propper_, Aug 17 2005