

A098153


Summarize the previous term in binary (in increasing order).


2



1, 11, 101, 10101, 100111, 1001001, 1000111, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001
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OFFSET

1,2


COMMENTS

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.


LINKS

Table of n, a(n) for n=1..27.


FORMULA

a(n) = 1101001 for all n >= 8 (see example).


EXAMPLE

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)=...).


CROSSREFS

Cf. A098154 (ternary), A098155 (base 4), A005151 (decimal and digit strings for all other bases b >= 5).
Sequence in context: A080176 A064490 A080439 * A020449 A089971 A082620
Adjacent sequences: A098150 A098151 A098152 * A098154 A098155 A098156


KEYWORD

base,easy,nonn


AUTHOR

Rick L. Shepherd, Aug 29 2004


STATUS

approved



