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%I A001141
%S A001141 5,15,1115,3115,132115,1113122115,311311222115,13211321322115,
%T A001141 1113122113121113222115,31131122211311123113322115,
%U A001141 132113213221133112132123222115
%N A001141 Describe the previous term! (method A - initial term is 5).
%C A001141 Method A = 'frequency' followed by 'digit'-indication.
%D A001141 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 A001141 S. R. Finch, Mathematical Constants, Cambridge, 2003, pp. 452-455.
%D A001141 I. Vardi, Computational Recreations in Mathematica. Addison-Wesley, Redwood 
               City, CA, 1991, p. 4.
%H A001141 S. R. Finch, <a href="http://algo.inria.fr/bsolve/constant/cnwy/cnwy.html">
               Conway's Constant</a>
%e A001141 E.g. the term after 3115 is obtained by saying "one 3, two 1's, one 5", 
               which gives 132115.
%t A001141 RunLengthEncode[ x_List ] := (Through[ {First, Length}[ #1 ] ] &) /@ 
               Split[ x ]; LookAndSay[ n_, d_:1 ] := NestList[ Flatten[ Reverse 
               /@ RunLengthEncode[ # ] ] &, {d}, n - 1 ]; F[ n_ ] := LookAndSay[ 
               n, 5 ][ [ n ] ]; Table[ FromDigits[ F[ n ] ], {n, 1, 11} ] - Zerinvary 
               Lajos (zerinvarylajos(AT)yahoo.com), Mar 21 2007
%Y A001141 Cf. A001155, A005150, A006751, A006715, A001140, A001143, A001145, A001151, 
               A001154.
%Y A001141 Sequence in context: A053926 A112273 A112515 this_sequence A138489 A022509 
               A138074
%Y A001141 Adjacent sequences: A001138 A001139 A001140 this_sequence A001142 A001143 
               A001144
%K A001141 nonn,base,easy,nice
%O A001141 1,1
%A A001141 N. J. A. Sloane (njas(AT)research.att.com).

    
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Last modified December 20 16:54 EST 2009. Contains 171081 sequences.


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