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A112377
A self-descriptive fractal sequence: if 1 is subtracted from every term and any zero terms are omitted, the original sequence is recovered (this process may be called "lower trimming").
6
1, 2, 1, 1, 3, 1, 2, 1, 2, 1, 1, 1, 4, 1, 2, 1, 1, 3, 1, 2, 1, 1, 3, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 5, 1, 2, 1, 1, 3, 1, 2, 1, 2, 1, 1, 1, 4, 1, 2, 1, 1, 3, 1, 2, 1, 2, 1, 1, 1, 4, 1, 2, 1, 1, 3, 1, 2, 1, 1, 3, 1, 2, 1, 1, 3, 1, 2, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 1, 6, 1, 2, 1, 1, 3, 1, 2, 1, 2, 1
OFFSET
0,2
COMMENTS
This sequence is also self-descriptive, in that each element gives the number of zeros that were removed before it. The indices where the sequence hits a new maximum value (2 at the 2nd position, 3 at the 5th position, 4 at the 13th, 5 at the 34th, etc.) are every second Fibonacci number.
MATHEMATICA
lowertrim[list_] := DeleteCases[list - 1, 0];
Nest[Flatten[Append[#, {ConstantArray[1, #[[Length[lowertrim[#]] + 1]]], #[[Length[lowertrim[#]] + 1]] + 1}]] &, {1, 2}, 15] (* Birkas Gyorgy, Apr 27 2011 *)
CROSSREFS
KEYWORD
nonn,easy,nice
AUTHOR
Kerry Mitchell, Dec 04 2005
STATUS
approved