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 A001388 Describe the previous term (in base 3)!. 4
 1, 11, 21, 1211, 111221, 1012211, 1110112221, 101102110211, 111021101221101221, 1011012211011222110112211, 1110211011222110211022110212221, 10110122110211022110122110222110121110211 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS John Cerkan, Table of n, a(n) for n = 1..23 EXAMPLE To get the 6th term, for example, note that the 5th term has three (10 in ternary!) 1's, two (2) 2's and one (1) 1, giving 10 1 2 2 1 1. MATHEMATICA a[1] := 1; a[n_] := a[n] = FromDigits[Flatten[{IntegerDigits[Length[#], 3], First[#]}& /@ Split[IntegerDigits[a[n-1]]]]]; Map[a, Range[25]] (* Peter J. C. Moses, Mar 24 2013 *) CROSSREFS Cf. A005150. Sequence in context: A007890 A063850 A005150 * A110393 A202627 A257491 Adjacent sequences:  A001385 A001386 A001387 * A001389 A001390 A001391 KEYWORD nonn,base,easy AUTHOR STATUS approved

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