A098154 Summarize the previous term in ternary (in increasing order).

1, 11, 21, 1112, 10112, 1010112, 2011112, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122

Offset

1,2

Comments

Similar to A005151 but uses base 3: Let a(1)=1. Describing a(1) as "one 1" again gives a(2)=11 (same digit string as A005151 and similar sequences). Likewise, a(3) and a(4) have same digit strings as all but the binary sequence, but describing a(4) as "three 1's, one 2" gives a(5)=10112 when the frequency of digit occurrence is written in ternary and followed by the digit counted.

Links

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

Formula

a(n) = 1011122 for all n >= 8 (see example).

Example

Summarizing a(8) = 1011122 in increasing digit order, there are "one 0, four 1's, two 2s", so concatenating 1 0 11 1 2 2 gives a(9) = 1011122 (=a(10)=a(11)=...).

Crossrefs

Cf. A098153 (binary), A098155 (base 4), A005151 (decimal and digit strings for all other bases b >= 5).

Sequence in context: A006711 A005151 A098155 * A007890 A063850 A005150

Adjacent sequences: A098151 A098152 A098153 * A098155 A098156 A098157

Keyword

base,easy,nonn

Author

Rick L. Shepherd, Aug 29 2004

Status

approved