%I #3 Mar 30 2012 17:36:43
%S 1,11,101,10101,100111,1001001,1000111,1101001,1101001,1101001,
%T 1101001,1101001,1101001,1101001,1101001,1101001,1101001,1101001,
%U 1101001,1101001,1101001,1101001,1101001,1101001,1101001,1101001,1101001
%N Summarize the previous term in binary (in increasing order).
%C Similar to A005151 but uses base 2: Let a(1)=1. Describing a(1) as "one 1" again gives a(2)=11 (same digit string as A005151 and similar sequences), but describing a(2) as "two 1's" gives a(3)=101 when the frequency of digit occurrence is written in binary and followed by the digit counted.
%F a(n) = 1101001 for all n >= 8 (see example).
%e Summarizing a(8) = 1101001 in increasing digit order, there are "three 0's, four 1's", so concatenating 11 0 100 1 gives a(9) = 1101001 (=a(10)=a(11)=...).
%Y Cf. A098154 (ternary), A098155 (base 4), A005151 (decimal and digit strings for all other bases b >= 5).
%K base,easy,nonn
%O 1,2
%A _Rick L. Shepherd_, Aug 29 2004