%I A001151
%S A001151 8,18,1118,3118,132118,1113122118,311311222118,13211321322118,
%T A001151 1113122113121113222118,31131122211311123113322118,
%U A001151 132113213221133112132123222118
%N A001151 Describe the previous term! (method A - initial term is 8).
%C A001151 Method A = 'frequency' followed by 'digit'-indication.
%D A001151 J. H. Conway, The weird and wonderful chemistry of audioactive decay,
in T. M. Cover and Gopinath, eds., Open Problems in Communication
and Computation, Springer, NY 1987, pp. 173-188.
%D A001151 S. R. Finch, Mathematical Constants, Cambridge, 2003, pp. 452-455.
%D A001151 I. Vardi, Computational Recreations in Mathematica. Addison-Wesley, Redwood
City, CA, 1991, p. 4.
%H A001151 S. R. Finch, <a href="http://algo.inria.fr/bsolve/constant/cnwy/cnwy.html">
Conway's Constant</a>
%e A001151 E.g. the term after 3118 is obtained by saying "one 3, two 1's, one 8",
which gives 132118.
%t A001151 RunLengthEncode[x_List] := (Through[{First, Length}[ #1]] &) /@ Split[x];
LookAndSay[n_, d_: 1] := NestList[Flatten[Reverse /@ RunLengthEncode[
# ]] &, {d}, n - 1]; F[n_] := LookAndSay[n, 8][[n]]; Table[FromDigits[F[n]],
{n, 1, 11}] [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com),
Jul 08 2009]
%Y A001151 Cf. A001155, A005150, A006751, A006715, A001140, A001141, A001143, A001145,
A001154.
%Y A001151 Sequence in context: A151351 A113563 A092692 this_sequence A138492 A022512
A146299
%Y A001151 Adjacent sequences: A001148 A001149 A001150 this_sequence A001152 A001153
A001154
%K A001151 nonn,base,easy,nice
%O A001151 1,1
%A A001151 N. J. A. Sloane (njas(AT)research.att.com).
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