OFFSET
1,1
COMMENTS
The 'look-and-repeat' sequence A225330, with seed 2. The variant A225331 with the same seed 2 gives this same sequence.
It describes at each step the preceding digits by repeating the frequency number.
The sequence is determined by triples of digits. The first two terms of a triple are the repeated count and the last term is the digit.
a(n) is always equal to 1, 2, 3, or 5. No series of four identical digits happens in the sequence, nor any of five 5's.
Applying the look-and-repeat principle to the sequence itself, it is simply shift one rank to the left.
EXAMPLE
a(1) = 2, you then see "one 2" and repeating "one", a(2) = a(3) = 1 (one) and a(4) = 2; you have then two 1's, so 2, 2, 1; then three 2, so 3, 3, 1, etc.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jean-Christophe Hervé, May 12 2013
STATUS
approved