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%I A001143
%S A001143 6,16,1116,3116,132116,1113122116,311311222116,13211321322116,
%T A001143 1113122113121113222116,31131122211311123113322116,
%U A001143 132113213221133112132123222116
%N A001143 Describe the previous term! (method A - initial term is 6).
%C A001143 Method A = 'frequency' followed by 'digit'-indication.
%D A001143 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 A001143 S. R. Finch, Mathematical Constants, Cambridge, 2003, pp. 452-455.
%D A001143 I. Vardi, Computational Recreations in Mathematica. Addison-Wesley, Redwood 
               City, CA, 1991, p. 4.
%H A001143 S. R. Finch, <a href="http://algo.inria.fr/bsolve/constant/cnwy/cnwy.html">
               Conway's Constant</a>
%e A001143 E.g. the term after 3116 is obtained by saying "one 3, two 1's, one 6", 
               which gives 132116.
%t A001143 RunLengthEncode[ x_List ] := (Through[ {First, Length}[ #1 ] ] &) /@ 
               Split[ x ]; LookAndSay[ n_, d_:1 ] := NestList[ Flatten[ Reverse 
               /@ RunLengthEncode[ # ] ] &, {d}, n - 1 ]; F[ n_ ] := LookAndSay[ 
               n, 6 ][ [ n ] ]; Table[ FromDigits[ F[ n ] ], {n, 1, 11} ] - Zerinvary 
               Lajos (zerinvarylajos(AT)yahoo.com), Mar 21 2007
%Y A001143 Cf. A001155, A005150, A006751, A006715, A001140, A001141, A001145, A001151, 
               A001154.
%Y A001143 Sequence in context: A080809 A118949 A053334 this_sequence A138490 A022510 
               A120930
%Y A001143 Adjacent sequences: A001140 A001141 A001142 this_sequence A001144 A001145 
               A001146
%K A001143 nonn,base,easy,nice
%O A001143 1,1
%A A001143 N. J. A. Sloane (njas(AT)research.att.com).

    
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Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


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