%I A103618
%S A103618 10,12,11,12,8,10,10,10,10,10,9,11,10,11,7,9,9,9,9,9,6,10,0,9,6,6,6,6,
6,
%T A103618 6,8,11,9,10,6,6,9,9,9,9,9
%N A103618 Number of steps required for n to reach a digit count invariant or cycle
loop.
%H A103618 Madras Math., <a href="http://www.madras.fife.sch.uk/maths/descriptive8.html">
Descriptive Numbers: Table of results</a>
%e A103618 a(10)=9 because we have the 9-step chain 10 -> 1011 -> 1031 -> 102113
-> 103112113 -> 10411223 -> 1031221314 -> 1041222314 -> 1031321324
-> 1031223314, the latter being autobiographical, hence invariant.
Also, a(40)=9 since we have the digit count iteration 40 -> 1014
-> 102114 -> 10311214 -> 1041121314 -> 1051121324 -> 104122131415
-> 105122132415 -> 104132131425 -> 104122232415 <-> 103142132415,
ending in a 2-cycle loop.
%Y A103618 Cf. A005151, A047841, A104785, A104786, A104787.
%Y A103618 Sequence in context: A064841 A064795 A078285 this_sequence A031166 A098732
A109394
%Y A103618 Adjacent sequences: A103615 A103616 A103617 this_sequence A103619 A103620
A103621
%K A103618 more,nonn
%O A103618 1,1
%A A103618 Lekraj Beedassy (blekraj(AT)yahoo.com), Mar 25 2005
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