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A098154
Summarize the previous term in ternary (in increasing order).
2
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.
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
KEYWORD
base,easy,nonn
AUTHOR
Rick L. Shepherd, Aug 29 2004
STATUS
approved