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A072147
Records for the length of the preperiodic part of the 'Reverse and Subtract' trajectories.
2
0, 1, 2, 6, 7, 12, 13, 18, 25, 40, 45, 47, 48, 49, 55, 56, 60, 62, 63, 64, 66, 71, 72, 75, 78, 81, 106, 108, 111, 112, 114, 115, 119, 121, 122, 130, 132, 133, 135, 147, 148, 149, 151, 156
OFFSET
1,3
COMMENTS
Successive maxima in sequence A072137. A072146 gives the corresponding starting points. - This sequence is a weak analog of A065199, which uses 'Reverse and Add'.
EXAMPLE
6 is a record, since the preperiodic part of the trajectory of 13 has length 6 and for k < 13 the preperiodic part has a smaller length (at most 2).
CROSSREFS
KEYWORD
base,more,nonn
AUTHOR
Klaus Brockhaus, Jun 24 2002
EXTENSIONS
a(18) inserted, a(25) corrected, a(29) through a(44) added by Alexander Pesch (alex-physics(AT)gmx.net), May 29 2007
Edited by N. J. A. Sloane, Dec 01 2007
STATUS
approved